If the terminal velocity of a 50.0-kg skydiver is 60.0 m/s, what is the value ofb? If youve been on a roller coaster, youve experienced the slow climb up that first big hill on the tracks. The Conservation of Energy equation between Point A and Point B reduces to the kinematic equation v2 = v02 + 2a(x), although it takes some effort to prove that correctly given that velocity and displacement are vectors. An object (A) of mass m = 28.5 kg is moving in a direction that makes angle of 62 north of west, Q:Self-Paced Problem 1: What type of movement could be caused by this force? (b) Calculate the centripetal acceleration. Consider a linear spring, as in Figure 7.7(a), with mass M uniformly distributed along its length. for Part B for Part B undo for Part B redo for Part B reset for Part B keyboard shortcuts for Part B help for Part B Why is there a voltage on my HDMI and coaxial cables? Assume that the force is exerted parallel to her legs. (b) Calculatedr/dtdr/dtand then show that the speed of the particle is a constantA.A. Express your answer numerically, in meters. It is equally correct to include it. each. (Figure 1)A roller-coaster car may be represented by a block of mass 50.0 kg . The coefficient of friction betweenm1m1and the inclined surface isk=0.40.k=0.40. A) 5.0 m/s2 weight at a distance of Watch the mass inside the tube carefully, (1 kg = 2.2 lbs.) 8 Potential Energy and Conservation of Energy, Thermal Expansion in Two and Three Dimensions, Vapor Pressure, Partial Pressure, and Daltons Law, Heat Capacity of an Ideal Monatomic Gas at Constant Volume, Chapter 3 The First Law of Thermodynamics, Quasi-static and Non-quasi-static Processes, Chapter 4 The Second Law of Thermodynamics, Creative Commons Attribution 4.0 International License, [latex]{f}_{\text{s}}\le {\mu }_{\text{s}}N[/latex], [latex]{F}_{\text{c}}=m\frac{{v}^{2}}{r}\enspace\text{or}\enspace{F}_{\text{c}}=mr{\omega }^{2}[/latex], [latex]\text{tan}\,\theta =\frac{{v}^{2}}{rg}[/latex], [latex]{F}_{D}=\frac{1}{2}C\rho A{v}^{2}[/latex], [latex]{F}_{\text{s}}=6\pi r\eta v[/latex]. There are no significant non-conservative forces (like friction) present between Points A and B, and so the work done by non-conservative forces is about zero. (a) What is the final velocity of a car originally traveling at 50.0 km/h that decelerates at a rate of0.400m/s20.400m/s2for 50.0 s? 15.0 V The contestant now pulls the block of ice with a rope over his shoulder at the same angle above the horizontal as shown below. the initial height 54.0 m is great enough so that the car never loses contact arrow_forward Literature guides Concept explainers Writing guide Popular textbooks Popular high school textbooks Popular Q&A Business Accounting Economics Finance Leadership Management Marketing Operations Management Engineering Bioengineering Chemical Engineering Civil Engineering At the start of the ride, when $v=0$, the Total Energy $T$ was: $T = mgh_1$ and when the car reaches the lowest point $h_3$, then: Note something important here: the expression for $v$ does not contain the mass $m$ of the car (and riders). Webto the floor of the roller coaster at all times, allowing the mass to move up and down in the tube freely.) Draw the side view of your roller coaster on graph paper. A particle of mass 0.50 kg starts moves through a circular path in thexy-plane with a position given byr(t)=(4.0cos3t)i+(4.0sin3t)jr(t)=(4.0cos3t)i^+(4.0sin3t)j^whereris in meters andtis in seconds. We say that the car at that point has a Potential Energy $U$ according to: $U=mgh_1$, where $g=9.81\:\mathrm{ms^{-2}}$ the Earth's acceleration constant, $m$ is the mass of the car (and riders) and $h_1$ that height above the reference line. a force of 50 lbf. The coefficient of friction is80%80%of that for the static case. A plumb bob hangs from the roof of a railroad car. (b) What is the tension in the string? If non-conservative forces are either known or small and if energy is converted from one form to another between the locations, then any time you relate speed and position of an object at two different points conservation of energy is the most direct way to understand the problem. Gravitational potential energy can be either negative or positive, depending on whether the object is below or above the h = 0 point. Distance (cm) For that reason I'm very surprised that a roller coaster operator would specify any loads, instead of relying on a fail safe design. The weight of roller coaster carts varies greatly with the roller coaster style. If the cart starts at a height h1 = 10m, how much must the. During a moment of inattention, the mini-fridge slides down a 35 degree incline at constant speed when she applies a force of 25 N acting up and parallel to the incline. Explain. View Available Hint(s) Submit Provide Feedback or Part B for Part J undo for Part B redo for Part B reset for Part B keyboard shortcuts for Part B help for Part B m, Principles of Physics: A Calculus-Based Text. The best answers are voted up and rise to the top, Not the answer you're looking for? that Suppose you have a 120-kg wooden crate resting on a wood floor, with coefficient of static friction 0.500 between these wood surfaces. Be sure to draw diagrams, resolve all force vectors into horizontal and vertical components, and draw a free-body diagram. (b) Calculate the force in the coupling between the dogs and the sled. Intamin (older) cars were quite heavy around 2800 each and (newer) around 2500 each. The car is released from rest at a height h = 54.0 m above the Such a large normal force is dangerous and very uncomfortable for the riders. The force of The energy conversion chain for this motion is, gravitational potential energykinetic energy + gravitational potential energy. The position of a particle is given byr(t)=A(costi+sintj),r(t)=A(costi^+sintj^),whereis a constant. Before Collision There is friction between the two blocks (coefficient of friction). (b) Find the velocity of the box as it reaches the end of the plane, if the length of the plane is 2 m and the box starts at rest. To be stable, the force exerted by the ground must be on a line going through the center of gravity. Human nerve cells have a net negative charge and the material WebAs it is released, its velocity is 4.4 m/s. 1 of 1 Assume no energy is lost due to dissipative forces such as friction. A 1000 kg roller coaster begins on a 10 m tall hill with an initial velocity of 6m/s and travels down before traveling up a second hill. Take care. The region and polygon don't match. WebRoller coaster trains have wheels that run on the sides (side friction or guide wheels) and underneath the track (upstop, underfriction, or underlocking wheels) as well as on top of it (road or running wheels); these lock the train to the tracks and prevent it from jumping the track.The side wheels can be mounted on the outside or inside of the train, depending on It takes 12 s to fall a distance of 0.60 m. Calculate the viscosity of the oil. > coaster carriage weighs? The roller-coaster track includes a circular loop of radius R in a vertical plane. 1 Answer Michael Nov 9, 2016 #sf(41color(white)(x)"m/s")# Explanation: The potential energy of the roller coaster is converted into kinetic energy when it reaches the bottom. Energy is almost always the most efficient way to approach these problems as long as enough information is given. How much do the roller coaster carts weigh? Suppose that the resistive force of the air on a skydiver can be approximated byf=bv2.f=bv2. Calculate the velocity a spherical rain drop would achieve falling from 5.00 km (a) in the absence of air drag (b) with air drag. > coaster carriage weighs? Draw the side view of your roller coaster on graph paper. A 35.0-kg dolphin decelerates from 12.0 to 7.50 m/s in 2.30 s to join another dolphin in play. Submit (a) On dry concrete. = mgh where m is the mass of your cart in grams, h is the height of your track and g=9.8 N/kg to calculate the potential energy. (c) Compare each force with his weight. A mysterious force acts on all particles along a particular line and always points towards a particular point P on the line. Also, if the object is on an inclined plane, the normal force is always less than the full weight of the object. Get access to millions of step-by-step textbook and homework solutions, Send experts your homework questions or start a chat with a tutor, Check for plagiarism and create citations in seconds, Get instant explanations to difficult math equations, A machine is a device that accepts energy in some available form and utilizes it to do a type of work. For small objects (such as a bacterium) moving in a denser medium (such as water), the drag force is given by Stokes law. #mgh/2=KE_#(B)#=1/2 m v_B^2# One can measure the time it takes for a particle to fall a certain distance and then use Stokes law to calculate the viscosity of the liquid. Part of riding a bicycle involves leaning at the correct angle when making a turn, as seen below. WebThe value of 30 m/s is reasonable for motion of a roller-coaster. b) How hard does it press against the track at point B. (Note that this acceleration is independent of mass.). A banked highway is designed for traffic moving at 90.0 km/h. Some problems contain several physical quantities, such as forces, acceleration, velocity, or position. What is the maximum force of friction under such conditions? (a) Find its initial acceleration if it takes off vertically. A roller coaster car with its passengers has a mass of 220 kg and it goes through a series of horizontal and vertical curves. What is (a) the acceleration of each block and (b) the tension in the string? A roller coaster car starts from rest at the top of a track 30.0 m long and inclined at20.020.0to the horizontal. rev2023.3.3.43278. = 5 9.81 * 5 Joules. B. Most roller-coasters dont care about too tall, In this case, the changing position of the roller-coaster reflected a change in the energy of the system, we are not asked to find time, and there are no significant unknown energy losses from the system. A 75.0-kg woman stands on a bathroom scale in an elevator that accelerates from rest to 30.0 m/s in 2.00 s. (a) Calculate the scale reading in newtons and compare it with her weight. (a) What are the drag forces at 70 km/h and 100 km/h for a Toyota Camry? A car rounds a curve and encounters a patch of ice with a very low coefficient of kinetic fiction. A 2.00 kg block (mass 1) and a 4.00 kg block (mass 2) are connected by a light string as shown; the inclination of the ramp is40.040.0. White light is capable, A:To answer A skydiver is at an altitude of 1520 m. After 10.0 seconds of free fall, he opens his parachute and finds that the air resistance,FDFD, is given by the formulaFD=bv,FD=bv,wherebis a constant andvis the velocity. If an object is to rest on an incline without slipping, then friction must equal the component of the weight of the object parallel to the incline. A. (d) How high has the elevator moved above its original starting point, and what is its final velocity? Shown below are two carts connected by a cord that passes over a small frictionless pulley. How does Charle's law relate to breathing? No. While some can be, most are powered with gravity. How fast is the coaster moving? As a result, the particle moves along a straight path from a Cartesian coordinate of (0m,0m) to (5m,6m) . One depended upon the speed, while the other was proportional to the square of the speed. If each block has an acceleration of2.0m/s22.0m/s2to the right, what is the magnitudeFof the applied force? Since the work of the gravitational force mg is path Independent, what did the King of the Apes gain in using stairs? Express your answer numerically, in joules. If the top of the next hill is 13 meters, what is the kinetic energy of the roller coaster on this hill? Arrow cars (2 seaters) weighed around (a) What is the force of the car seat on the child at point A? (b) How much time elapses before it reaches the bottom of the track? 20 A double-incline plane is shown below. (b) What is unreasonable about the result? A block of mass 0.500 kg is pushed against a horizontal spring of negligible mass until the spring is compressed a distance x (Fig. When the car takes a turn, the track must be able to supply a force $F_c$ known as the centripetal force in order to keep the car on the track: $\large{F_c=\frac{mv^2}{R}}$, where $R$ is the radius of the bend. Therefore, there is no need to solve for the speed of the rollercoaster at Point C. You can set up the Conservation of Energy equation between Point A and Point D. However, it is perfectly fine to solve the intermediate step of finding the velocity at Point C if you like. WebA 515-kg (empty weight), single cart roller coaster carrying 4 passengers (average mass of 64 kg per person) is towed to the top of a hill. No. A contestant in a winter sporting event pushes a 45.0-kg block of ice across a frozen lake as shown below. The values for Point A can be put into the equation directly from your picture. Rolling friction for trains is small, and consequently, trains are very energy-efficient transportation systems. (a) If half of the weight of a small1.00103-kg1.00103-kgutility truck is supported by its two drive wheels, what is the maximum acceleration it can achieve on dry concrete? Modern roller coasters have vertical loops like the one shown here. Mass is present in all terms of the equation, and so it can be divided out. Only two forces act on the mass. Consider the 65.0-kg ice skater being pushed by two others shown below. Explain how this allows the curve to be taken at the greatest speed. 2003-2023 Chegg Inc. All rights reserved. WebA 725 kg roller coaster car is at the top of a roller coaster car is at the top of a roller coaster as shown below. (d) If the elevator had no brakes and the cable supporting it were to break loose so that the elevator could fall freely, what would the spring scale read? What is it? As he got older, he decided to build and use a staircase instead. Calculate the tension in the two ropes if the person is momentarily motionless. When the freight car begins to move, the string makes an angle of35.035.0with the vertical. (b) What force would he have to exert if the steel parts were oiled? K = Race car drivers routinely cut corners, as shown below (Path 2). Friction is negligible. At what angle relative to the vertical does the plumb bob hang? (c) What minimum speed is required to keep the child in his seat at point A? For the sake of simplicity, assume that your roller coaster track never, a. General Physics Using Calculus I by OpenStax is licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted. What is the weight of the space probe on that planet? WebFind many great new & used options and get the best deals for LEGO FRIENDS: Amusement Park Roller Coaster (41130) Complete Boxed Retired! Bx=1.3 T Define centripetal force. height h, Q:As shown below, a wire loop is immersed in a 0.8 T B-field (the direction of the field is shown in, Q:The 20-g bullet is travelling at 400 m/s when it becomes embedded in the Height is #h//2,:. Seriously, I would not trust rides like that. The mass of the roller coaster below is 80 kg. An object with massmmoves along thex-axis. (b) What is the maximum force that can be applied upward along the plane on the rope and not move the block? m/s Yup, though they are admitedly a rare breed. (b) At point B #approx 26.94 m//s# (The scale exerts an upward force on her equal to its reading.) Jane, whose mass is 50.0 kg, needs to swing across a river (having width D) filled with person-eating crocodiles to save Tarzan from danger. solid sphere having charge (q1)=+2.08 fC (b) Calculate his acceleration while he is straightening his legs. How do you find density in the ideal gas law. Greater than 10 pounds Make some assumption on their frontal areas and calculate their terminal velocities. (d) #41 m#. Assume Tarzan has a mass of 80.0 kg. If the gravitational potential energy of the car-Earth system is taken to be zero at C, what is its value How far away, A:Radiusofnucleus=n=10-15mRadiusoforbitalelectron=e=10-10mScalemodelradiusofnucleus=N=1.4, Q:Determine the time constant of the LR circuit. (a) Find the direction and magnitude ofFtot,Ftot,the total force exerted on her by the others, given that the magnitudesF1F1andF2F2are 26.4 N and 18.6 N, respectively. Find the kinetic energy K of the car at the top of the loop. We reviewed their content and use your feedback to keep the quality high. To learn more, see our tips on writing great answers. In this problem, you are first asked to find a speed of a roller-coaster when you are given information about how its height changes. KEA + PEA = KED + PED - Wnc (a) At point A #=18 m//s# Because there is no friction over this portion of the track, the only energy conversion that takes place is between kinetic energy and gravitational potential energy. Include a free-body diagram in your solution. P7.81). Thanks for contributing an answer to Physics Stack Exchange! given no change in kinetic energyKE=0 >. Many amusement parks have rides that make vertical loops like the one shown below. Because it is released from rest, its starting velocity is zero. How to react to a students panic attack in an oral exam? This is not a large frictional force for such a massive system. Energy is the same top and bottom, Ke at bottom, Pe at top This is the principal mode of operation of roller coasters (without any propulsion systems installed in the cars) which allows them to negotiate a series of slopes and hills without running out of energy. You may assume that the weight of the car is evenly distributed on all four tires and that the coefficient of static friction is involvedthat is, the tires are not allowed to slip during the deceleration. A) 250. A small diamond of mass 10.0 g drops from a swimmers earring and falls through the water, reaching a terminal velocity of 2.0 m/s. The, Q:, Problem 7: A computer disk starts from rest at time t = 0 and accelerates uniformly for 0.500 s, A:Given data- around the world. (b) What is the force of the car seat on the child at point B? If the thrust of the motor is a constant force of 40.0 N in the direction of motion, and if the resistive force of the water is numerically equivalent to 2 times the speedvof the boat, set up and solve the differential equation to find: (a) the velocity of the boat at timet; (b) the limiting velocity (the velocity after a long time has passed). Particles in liquids achieve terminal velocity quickly. If a car takes a banked curve at less than the ideal speed, friction is needed to keep it from sliding toward the inside of the curve (a problem on icy mountain roads). A roller coaster has a mass of 275 kg. Find the following. Because there is no friction between Points A and C, the energy of the rollercoaster remains constant over that portion of the motion. (b) What centripetal force is exerted if the merry-go-round rotates at 3.00 rev/min and he is 8.00 m from its center? (b) Calculate the magnitude ofF.F. What magnitude force must act up and parallel to the incline for the bin to move down the incline at constant velocity? In a television commercial, a small, spherical bead of mass 4.00 g is released from rest att=0t=0in a bottle of liquid shampoo. (c) Which premises are unreasonable or inconsistent? Note: Attach graphical, Q:A ring-shaped conductor with radius a = 2.20 cm has a h hmin= A 30.0-kg girl in a swing is pushed to one side and held at rest by a horizontal forceFFso that the swing ropes are30.030.0with respect to the vertical. #V_(Total)#(B)#=sqrt(324+401.8)#. An airplane flying at 200.0 m/s makes a turn that takes 4.0 min. The two barges shown here are coupled by a cable of negligible mass. Mass cannot be divided out of this equation because it does not appear in all terms. A constant resultant force of(2.0i+4.0j)N(2.0i^+4.0j^)Nthen acts on the object for 3.0 s. What is the magnitude of the objects velocity at the end of the 3.0-s interval? First week only $4.99! > philadelphia tobbogan train cars weigh on average 800#'S FOR WOODEN COASTERS, > Hi, does anyone have any idea how much the average roller What is the speed of the roller coaster at point B? *Response times may vary by subject and question complexity. Angle of inclination for M1 is The incline has friction. Your question is solved by a Subject Matter Expert. Find the net force on the helicopter att=3.0s.t=3.0s. As shown below, ifM=6.0kg,M=6.0kg,what is the tension in the connecting string? A car is moving at high speed along a highway when the driver makes an emergency braking. (a) What is the maximum frictional force in the knee joint of a person who supports 66.0 kg of her mass on that knee? --------------------------------- To maintain a constant speed, the force provided by a cars engine must equal the drag force plus the force of friction of the road (the rolling resistance). Free shipping for many products! http://www.rcdb.com/ig222.htm?picture=6, > ok so how much does a normal car weigh in comparison to a just a thought, > Hi, does anyone have any idea how much the average roller If a light rain falls, what does this do to the control of the car? The car encounters a loop of radius R = 18.0 Two blocks connected by a string are pulled across a horizontal surface by a force applied to one of the blocks, as shown below. (a) A 22.0-kg child is riding a playground merry-go-round that is rotating at 40.0 rev/min. asked by Heylee Green November 30, 2020 1 answer What is the coefficient of kinetic friction between the child and the surface of the incline? Just like each said, as long as you can fit into t Continue Reading 6 Sponsored by The Penny Hoarder What is the ideal speed to take a 100.0-m-radius curve banked at a20.020.0angle? Suppose a steel ball bearing (density7.8103kg/m37.8103kg/m3, diameter 3.0 mm) is dropped in a container of motor oil. (c) With a slightly greater applied force, the block will slide up the plane. A freight train consists of two8.00105-kg8.00105-kgengines and 45 cars with average masses of5.50105kg.5.50105kg. Supposing the mass of the skier is 50 kg, what is the speed of the skier at point B ? What is its speed at the top of the loop? How would one calculate the lateral seat force experienced by a roller coaster rider if the turn were banked less than ideal? AL The force of gravity will cause it to speed up as it moves down the hill. (a) Find the acceleration of the system. A roller-coaster vehicle has a mass of 500 kg when fully loaded with passengers. When a body of mass 0.25 kg is attached to a vertical massless spring, it is extended 5.0 cm from its unstretched length of 4.0 cm. In one amusement park ride, riders enter a large vertical barrel and stand against the wall on its horizontal floor. Repeat the preceding problem for a car with four-wheel drive. Express your answer numerically, in meters. Is it a bug? Also use g = 10 m/s2. 2.2 Coordinate Systems and Components of a Vector, 3.1 Position, Displacement, and Average Velocity, 3.3 Average and Instantaneous Acceleration, 3.6 Finding Velocity and Displacement from Acceleration, 4.5 Relative Motion in One and Two Dimensions, 8.2 Conservative and Non-Conservative Forces, 8.4 Potential Energy Diagrams and Stability, 10.2 Rotation with Constant Angular Acceleration, 10.3 Relating Angular and Translational Quantities, 10.4 Moment of Inertia and Rotational Kinetic Energy, 10.8 Work and Power for Rotational Motion, 13.1 Newtons Law of Universal Gravitation, 13.3 Gravitational Potential Energy and Total Energy, 15.3 Comparing Simple Harmonic Motion and Circular Motion, 17.4 Normal Modes of a Standing Sound Wave, 1.4 Heat Transfer, Specific Heat, and Calorimetry, 2.3 Heat Capacity and Equipartition of Energy, 4.1 Reversible and Irreversible Processes, 4.4 Statements of the Second Law of Thermodynamics. If the car goes over the top at just the right speed, gravity alone will supply the centripetal force. Simple friction is proportional to the normal force. Riders feel as if they are pinned to the wall by a force something like the gravitational force. Calculate the average acceleration of the potato in the tube as it goes from zero to the velocity found in (a). Continue to Step 2 to solve for the stopping force required to bring the roller coaster to rest at Point D. An average force of 4200 N is required to stop the roller-coaster by Point D when the brakes are applied at Point C. No further mathematical solution is required for this problem. Connect and share knowledge within a single location that is structured and easy to search. Example 3: In this rollercoaster question, the track is older, so the 15 kg cart experiences an average frictional force of 50 N while on the track. When the elevator is accelerating downward at3.8m/s23.8m/s2, the scale reads 60 N. (a) What is the mass of the backpack? What will be the velocity of a 56-kg person hitting the ground, assuming no drag contribution in such a short distance? Suppose the ride starts where the car is drawn at a height $h_1$ above a common reference line (like the horizon). It may not display this or other websites correctly. Roller coasters are therefore not built with circular loops in vertical planes. There is however one complication: my ideal scenario doesn't account for any energy losses due to friction between car and track or air drag losses. A 1.5-kg mass has an acceleration of(4.0i3.0j)m/s2.(4.0i^3.0j^)m/s2. The rotational velocity is 200.0 cm/s. Calculate the deceleration of a snow boarder going up a5.005.00slope, assuming the coefficient of friction for waxed wood on wet snow. Can any type of force (for example, tension, gravitational force, friction, and so on) be a centripetal force? If there is no significant non-conservative force (as is the case in the first question) then all three versions of the equation are equivalent. First week only $4.99! then at 5 meters up This makes physical sensestopping force takes energy out of the system and so In which types of motion would each of these expressions be more applicable than the other one? Still others may write it as KE1 + PE1 + Eadded to the system = KE2 + PE2 + Eleaving the system. It only takes a minute to sign up. ERROR: CREATE MATERIALIZED VIEW WITH DATA cannot be executed from a function. Assume there is no friction or air resistance between Points A and C. How fast is the roller-coaster moving at Point B? What is the ideal banking angle for a gentle turn of 1.20-km radius on a highway with a 105 km/h speed limit (about 65 mi/h), assuming everyone travels at the limit? Is the total mechanical energy conserved in a system that's a simplifying approximation of an actual roller coaster? at the best online prices at eBay! The mass of the block on the table is 4.0 kg and the hanging mass is 1.0 kg. Describe this process in more detail, in particular, explaining how it is related to the fact that kinetic friction is less than static friction. A converging mirror has a focal length of f = 18 cm. The existence of a maximum weight was mentioned in passing but I don't think a figure was stated (I'm guessing there's a figure written somewhere for riders and if you're over 200 kg or whatever you're out of luck.). Assume a coefficient of friction of 1.0. View Available Hint(s) Rotating and accelerated frames of reference are noninertial. (c) Determined2r/dt2d2r/dt2and show thatais given byac=r2.ac=r2. The coefficient of sliding friction is known to be 0.300 for this situation. While the transfer of energy between two machine par, In physics, work is the product of the net force in direction of the displacement and the magnitude of this displacement or it can also be defined as the energy transfer of an object when it is moved for a distance due to the forces acting on it in the d. 250 pF has a charge of magnitude 0.146 C on, Q:d) What is the magnitude and direction of Vem i? Neglecting frictional losses, what is the expected speed of the coaster as it passes over the top of the The force constant of the spring is 450 N/m. What is the direction of the force exerted on you by the car seat? (b) At point B. , A:Here maximum current is Imax=9.5A (a) At point A. (a) Show that(as defined as shown) is related to the speedvand radius of curvaturerof the turn in the same way as for an ideally banked roadwaythat is,=tan1(v2/rg).=tan1(v2/rg). This form of the equation works equally well for the first part of the problem (where Wnc = 0) and for the second question (where you need to solve for Wnc.). This requires greater and greater friction for steeper slopes. (Hint:The arm supplies centripetal force and supports the weight of the cage. Dont I need to know the coefficient of friction to solve for stopping force? 12.A system, A:as per bartebley Q.A guideline I have answer first three part .remaining part of question.Please. Find the change, Q:A 800 lb horse pulls a 200 lb cart with