Physics 011

Quiz#4A

Ayman A.Ghannam

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 Chapter 4 Practice Problems

 1

A 5-kg box is released on a 30 degree incline and accelerates down the incline at m/s^2. To the nearest tenth of a Newton, what is the friction force impeding its motion?

 2

A 13-kg box is released on a degree incline and accelerates down the incline at 1.5 m/s^2. To two decimal places, what is the coefficient of friction ?

 3

A fisherman yanks a fish straight up out of the water with an acceleration of 2 m/s^2 using very light fishing line that has a "test" value of pounds. The fisherman, unfortunately, loses the fish as the line snaps. To the nearest tenth of a kilogram what is the minimum mass of the fish?

 4

A 0.145-kg baseball traveling m/s strikes the catcher's mitt, which, in bringing the ball to rest, recoils backward 20 cm. To the nearest Newton, what was the magnitude of the average force applied by the ball on the glove?

 5

A 10 kg bucket is lowered by a rope in which there is Newtons of tension. What is the magnitude of the acceleration (to the nearest tenth of a m/s^2) of the bucket?

 6

An elevator (mass kg) is to be designed so that the maximum acceleration is 1.5 m/s^2. What is the maximum force ( to the nearest Newton) the motor needs to exert on the supporting cable?

 7

If the coefficient of kinetic friction between a -kg crate and the floor is 0.30, what horizontal force ( to the nearest Newton) is required to move the crate at a steady speed across the floor?

 8

A 13,000-kg helicopter accelerates upward at m/s^2 while lifting a 2000 pound car. To the nearest Newton, what is the lift force exerted by the air on the rotors?