A 70.0 kg box is being pulled along a horizontal surface. The coefficient of kinetic friction between the box and the ground is 0.250. What horizontal force must be exerted on the box for it to accelerate at 1.20 m/s2  A 70.0 kg box is being pulled along a horizontal surface. The coefficient of kinetic friction between the box and the ground is 0.250. What horizontal force must be exerted on the box for it to accelerate at 1.20 m/s2  234 N 256 N 125 N 323 N 432 N

A 200 kg crate rests on a floor with carpet. A tired worker pushes with a horizontal force of 600 N on the crate initially resting on a thick pile carpet. The coefficients of static and kinetic friction are 0.60 and 0.40, respectively. Find the magnitude of the frictional force exerted by the surface of the crate by the carpet. Hint: Which type of friction acts in this case? What are the properties of different kinds of friction? O 1176 N O 784 N O 600 N O 1960 N O 500 N TEALING knong

must be used? Ans: 39 N Question 12. A skier is pulled up a slope at a constant velocity by a tow bar. The slope is inclined at 24.2° with respect to the horizontal. The force applied to the skier by the tow bar is parallel to the slope. The skier's mass is 56.7 kg, and the coefficient of kinetic friction between the skis and the snow is 0.140. Find the magnitude of the force that the tow bar exerts on the skier. Ans: 299 N What is the

A student applies a 100 N force at an angle 30° below the horizontal to a block causing the block to move at a constant speed along a level ground. Which statement regarding the kinetic friction on the block is most accurate? 100 N 30 The kinetic friction force is negligible and can be rounded to 0 N. The kinetic friction force is equal to 100 N. The kinetic friction force is greater than 100 N. The kinetic friction force is less than 100 N. O O O O