Exam 5: Force and Motion I

A crate rests on a horizontal surface and a woman pulls on it with a 10-N force. Rank the situations shown below according to the magnitude of the normal force exerted by the surface on the crate, least to greatest.

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 lead block is suspended from your hand by a string. The reaction to the force of gravity on the block is the force exerted by the:

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 wooden block is dragged by a force along a rough steel plate, as shown below for two cases. The magnitude of the applied force is the same for both cases. The normal force in (ii), as compared with the normal force in (i) is:

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

A block slides down a frictionless plane that makes an angle of 30 $\degree$ with the horizontal. The acceleration of the block is:

Equal forces act on isolated bodies A and B. The mass of B is three times that of A. The magnitude of the acceleration of A is:

A 5-kg concrete block is lowered with a downward acceleration of 2.8 m/s² by means of a rope. The force of the block on the rope is:

A 90-kg man stands in an elevator that is moving up at a constant speed of 5.0 m/s. The force exerted by him on the floor is about:

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 $\degree$ above the horizontal the magnitude of the applied force is:

A force of 1 N is:

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:

An example of an inertial reference frame is:

The mass and weight of a body:

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:

You stand on a spring scale on the floor of an elevator. Of the following, the scale shows the highest reading when the elevator:

The standard 1-kg mass is attached to a compressed spring and the spring is released. If the mass initially has an acceleration of 5.6 m/s², the force of the spring has a magnitude of:

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

You are driving your car along the road and hit a patch that is so icy that there is effectively no friction between your tires and the road. Which statement is most accurate?