PPSC Lecturer of Physics Online Test 49 Solved MCQs

A car moves horizontally with a constant acceleration of 3m/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?

A man weighing 700 Nb is in an elevator that is accelerating upward at 4m/s2. The force exerted on him by the elevator floor is:

A sled is on an icy (frictionless) slope that is 30◦ above the horizontal. When a 40-N force, parallel to the incline and directed up the incline, is applied to the sled, the acceleration of the sled is 2.0m/s2, down the incline. The mass of the sled is:

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

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

A heavy steel ball B is suspended by a cord from a block of wood W. The entire system is dropped through the air. Neglecting air resistance, the tension in the cord is:

When a 40-N force, parallel to the incline and directed up the incline, is applied to a crate on a frictionless incline that is 30◦ above the horizontal, the acceleration of the crate is 2.0m/s2, up the incline. The mass of the crate is:

The “reaction” force does not cancel the “action” force because:

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

A 400-N steel ball is suspended by a light rope from the ceiling. The tension in the rope 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:

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

A 32-N force, parallel to the incline, is required to push a certain crate at constant velocity up a frictionless incline that is 30◦ above the horizontal. The mass of the crate is:

A 90-kg man stands in an elevator that has a downward acceleration of 1.4m/s2. The force exerted by him on the floor is about:

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

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

A book rests on a table, exerting a downward force on the table. The reaction to this force is:

A 1000-kg elevator is rising and its speed is increasing at 3m/s2. The tension force of the cable on the elevator is:

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 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:

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 applied force 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:

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