Exam 5: Force and Motion I

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 short 10-g string is used to pull a 50-g toy across a frictionless horizontal surface. If a 3.0 * 10^-2-N force is applied horizontally to the free end, the force of the string on the toy, at the other end, is:

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

A car moves horizontally with a constant acceleration of 3 m/s². A ball is suspended by a string from the ceiling of the car; the ball does not swing, being at rest with respect to the car. What angle does the string make with the vertical?

Two blocks are connected by a string and pulley as shown. Assuming that the string and pulley are massless, the magnitude of the acceleration of each block is:

Acceleration is always in the direction:

A constant force of 8.0 N is exerted for 4.0 s on a 16-kg object initially at rest. The change in speed of this object will be:

A feather and a lead ball are dropped from rest in vacuum on the Moon. The acceleration of the feather is:

The mass of a body:

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 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 5-kg block is suspended by a rope from the ceiling of an elevator accelerates downward at 3.0 m/s². The tension force of the rope on the block is:

A 25-N crate is held at rest on a frictionless incline by a force that is parallel to the incline. If the incline is 25 above the horizontal the magnitude of the normal force of the incline on the crate is:

An example of an inertial reference frame is:

Two forces, one with a magnitude of 3 N and the other with a magnitude of 5 N, are applied to an object. For which orientations of the forces shown in the diagrams is the magnitude of the acceleration of the object the least?

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:

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

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:

A ball with a weight of 1.5 N is thrown at an angle of 30above the horizontal with an initial speed of 12 m/s. At its highest point, the net force on the ball is:

A car travels east at constant velocity. The net force on the car is: