Exam 5: Force and Motion

Two blocks with masses m and M are pushed along a horizontal frictionless surface by a horizontal applied force as shown.The magnitude of the force of either of these blocks on the other is:

When a certain force is applied to the 1-kg standard mass its acceleration is 5.0 m/s².When the same force is applied to another object its acceleration is one-fifth as much.The mass of the object is:

A massless rope passes over a massless pulley suspended from the ceiling.A 4-kg block is attached to one end and a 5-kg block is attached to the other end.The acceleration of the 5-kg block is:

A circus performer of weight W is walking along a "high wire" as shown.The tension in the wire is:

A 13-N weight and a 12-N weight are connected by a massless string over a massless, frictionless pulley.The 13-N weight has a downward acceleration with magnitude equal to that of a freely falling body times:

A 70-N block and a 35-N block are connected by a string as shown.If the pulley is massless and the surface is frictionless, the magnitude of the acceleration of the 35-N block is:

A heavy ball is suspended as shown.A quick jerk on the lower string will break that string but a slow pull on the lower string will break the upper string.The first result occurs because:

When a 25-kg crate is pushed across a frictionless horizontal floor with a force of 200 N, directed 20° below the horizontal, the magnitude of the normal force of the floor on the crate is:

A 6-kg object is moving south.A net force of 12 N north on it result in the object having an acceleration of:

The "reaction" force does not cancel the "action" force because:

The block shown moves with constant velocity on a horizontal surface.Two of the forces on it are shown.A frictional force exerted by the surface is the only other horizontal force on the block.The frictional force is:

A 9000-N automobile is pushed along a level road by four students who apply a total forward force of 500 N.Neglecting friction, the acceleration of the automobile is:

A 25-N crate slides down a frictionless incline that is 25° above the horizontal.The magnitude of the normal force of the incline on the crate is:

Which of the following is true, according to Newton's second law?

A crane operator lowers a 16,000 N steel ball with a downward acceleration of 3 m/s².The tension in the cable is:

Two forces are applied to a 5.0-kg crate; one is 6.0 N to the north and the other is 8.0 N to the west.The magnitude of the acceleration of the crate is:

Two blocks weighing 250 N and 350 N respectively, are connected by a string that passes over a massless pulley as shown.The tension in the string is:

An object moving at constant velocity in an inertial frame must:

The inertia of a body tends to cause the body to:

A 1-N pendulum bob is held at an angle $\theta$ from the vertical by a 2-N horizontal force F as shown.The tension in the string supporting the pendulum bob is: