A cord is wrapped around a pulley that is shaped like a disk of mass mand radius r. The cord's free end is connected to a block of mass M. The block starts from rest and then slides down an incline that makes an angle 0 with the horizontal as shown in Figure P10.48. The coefficient of kinetic friction between block and incline is u. (a) Use energy methods to show that the block's speed as a function of position d down the incline is 4Mgd(sin 0 – µ cos 0) т+ 2M (b) Find the magnitude of the acceleration of the block in terms of µ, m, M, g, and 0. m M Figure P10.48

When a 78.0 kg skateboarded passes point P, his mechanical energy is 3.68 x 10^3 J relative to the ground.When he passes point Q he is moving at 8.15 m/s. How high is the skateboarder (relative to the ground) at point Q?  Assume that the skateboard rolls with negligible friction.

An object with a mass of 12.5 kg is moving along a rough horizontal surface. At a certain point it has 66 J of kinetic energy. If the coefficient of friction between the object and the surface is 0.44, how far will the object go beyond that point before coming to a stop? Express your answer in meters, to at least one digit after the decimal point. plz help and use g = 9.8

A box of 9kg is released from rest on a rough inclined plane and slides to the bottom. The plane is inclined at a 230 angle to the horizontal and it is 5.1 m high. The coefficient of kinetic friction between the box and the plane is 0.1. Use conservation of energy to determine the speed of the block as it reaches the bottom.

2 W S X In a hydroelectric dam, water falls 35 m and then spins a turbine to generate electricity. 3 E D 80 C $ 4 R 888 F V 96 5 T G ^ 6 B ▾ Part A What is AU of 1.0 kg of water? Express your answer with the appropriate units. View Available Hint(s) AU= -340 J Y Submit ▾ Part B ✓ Correct SOLVE: The change in the potential energy of 1.0 kg of water in falling 35 m m is H Suppose the dam is 80% efficient at converting the water's potential energy to electrical energy. How many kilograms of water must pass through the turbines each second to generate 48 MW of electricity? This is a typical value for a small hydroelectric dam. Express your answer in kilograms per second. ▸ View Available Hint(s) m 11s AU, -mgh=-(1.0 kg) (9.8 m/s²) (35 m) = -340 J = = Provide Feedback Submit MacBook Air Previous Answers & 7 N IG] ΑΣΦ | 3-4 U * 8 D-H I M @ JK ( 9 MOSISO DD O I भ ? O L kg/s command F10 P > ; C option + ? T I Next > delete re

(8c7p19) A cord is used to vertically lower an initially stationary block of mass M = 45 ką at a constant downward acceleration of q/7. When the block has fallen a distance d = 4.5 m, find the work done by the cord's force on the block. Submit Answer Tries 0/5 Find the work done by the weight of the block. Submit Answer Tries 0/5 Find the kinetic energy of the block. Submit Answer Tries 0/5 Find the speed of the block. Submit Answer Tries 0/5

Maria sets up a simple track for her toy block  (m = 0.30 kg)  as shown in the figure below. She holds the block at the top of the track, 0.54 m above the bottom, and releases it from rest.   (a) Neglecting friction, what is the speed of the block when it reaches the bottom of the curve (the beginning of the horizontal section of track)? m/s(b) If friction is present on the horizontal section of track and the block comes to a stop after traveling 0.80 m along the bottom, what is the magnitude of the friction force acting on the block? N

A 69.0-kg athlete leaps straight up into the air from a trampoline with an initial speed of 8.9 m/s. The goal of this problem is to find the maximum height she attains and her speed at half maximum height. Write the general equation for energy conservation and solve for the velocity at half the maximum height. Substitute and obtain a numerical answer.

A 5.80-kg block is set into motion up an inclined plane with an initial speed of v₁ = 8.20 m/s (see figure below). The block comes to rest after traveling d = 3.00 m along the plane, which is inclined at an angle of 0 = to the horizontal. V. (a) For this motion, determine the change in the block's kinetic energy. (b) For this motion, determine the change in potential energy of the block-Earth system. (c) Determine the friction force exerted on the block (assumed to be constant). N (d) What is the coefficient of kinetic friction?

A 50.2-g golf ball is driven from the tee with an initial speed of 58.0 m/s and rises to a height of 22.4 m. (a) Neglect air resistance and determine the kinetic energy of the ball at its highest point. (b) What is its speed when it is 7.23 m below its highest point? (a) Number (b) Number Units Units