A 100 kg skier starts from rest at the top of a ski slope that is 50 m long. If his final speed at the bottom of the slope is 10 m/s, where the bottom of the slope is 20 m below the top, what is the approximate average force of friction between the skis and the slope? 20 m 50 m O 300 N O 1500 N ○ 600 N ○ 750 N O 150 N

A skier starts going down a rocky hill that is inclined 30 degrees from the horizontal. It is 2 km long, and he starts with an initial speed of 5 m/s down the hill. If the coefficient of kinetic friction between his skis and the hill is 0.7: Does he make it to the bottom? If so, how long does it take?

A girl is swinging on a swing. At the highest point, she is 3.8 meters from the ground. At the lowest point, she is 0.5 meters from the ground. Neglecting friction and air resistance, what will be her maximum speed? 10.4 m 3.8 m 0.5 m O 8.6 m/s O 8.0 m/s O 3.13 m/s O 13.9 m/s Her maximum speed depends on her mass.

A boy shoves his stuffed toy zebra down a frictionless chute. It starts at a height of 1.27 m above the bottom of the chute with an initial speed of 1.07 m/s. The toy animal emerges horizontally from the bottom of the chute and continues sliding along a horizontal surface with a coefficient of kinetic friction of 0.223. How far from the bottom of the chute does the toy zebra come to rest? Assume g = 9.81 m/s2. E

An object of mass m=2 kg placed on a rough horizontal surface is given an initial speed of 10 m/s and comes to rest after covering a distance d=12m. The kinetic friction f_k is equal to: VA = 8m/sec VB = 0 fki A B 5.33 N 8.33 N 6.75 N 9.85 N 4.66 N d

A hockey puck with mass 0.166 kg is pushed across the ice with a constant force of 0.89 N. The coefficient of kinetic friction between the puck and the ice is 0.22. After a distance of 2.6 m, what is the puck's speed in m/s?

A roller-coaster car descends 38 m from its highest point to its lowest. Suppose that the car, initially at rest at the highest point, rolls down this track without friction. What speed will the car attain at the lowest point? Select one: O O 14 m/s 54 m/s 38 m/s 27 m/s

KE = mv², Ug = mgh, Us=kx², E = KE + Ug + Us, E₁ = Ef, Wfric Ffried, Ffric = HkN, Et-Wfric = Ef Problem 1: In the Figure below a block slides along a path that is without friction until the block reaches the section of length L = 0.75 m, which begins at height h = 2 m on a ramp of angle 0 = 30°. In that section, the coefficient of kinetic friction is 0.40. The block passes through point A with a speed of 8 m/sec. What is the speed of the block at point B (where the friction ends)? Answer: 3.5 m/sec B/ 0

A 20-kg sled is being pulled along the horizontal snow-covered ground by a horizontal force of 28 N. Starting from rest, the sled attains a speed of 2.6 m/s in 9.4 m. Find the coefficient of kinetic friction between the runners of the sled and the snow.

A piece of ice (m = 1 Kg) slides down the slope of a roof inclined at 50.0°. It starts from rest and slides 8.0 m along the roof, sliding off the edge at a height of 4.0 m above the level ground. The coefficient of kinetic friction is 0.14. V¡ = 0.0 m/s m = 500.0 g 8,0 m Hx = 0.14 30° 4.0 m (a) Draw a free-body diagram of the ice as it is sliding along the roof. (b) Calculate the acceleration of the object. (c)With what speed does it leave the roof?