oct/nov 2021 physics

A student is taking some measurements.

Which measurement is taken directly using a micrometer screw gauge?

• 0.52 g /mm2

• 0.52 g /mm3

• 0.52 mm

• 0.52 mm2

Which graph represents an object that is moving at constant speed?

• A

• B

• C

• D

In which situation does object X have a greater mass than object Y?

• Object X is in a larger gravitational field than object Y and both have the same weight.

• Object X shows a greater resistance to change in motion than object Y and both experience

  the same resultant force.

• Object X has a lower density than object Y and both occupy the same volume.

• Object X moves at a greater speed than object Y and both possess the same kinetic energy.

Which substance in the table has the lowest density?

• A

• B

• C

• D

Three simple machines are shown.

Which machines are an application of the moment of a force?

• 1, 2 and 3

• 1 and 2 only

• 1 and 3 only

• 2 and 3 only

A spring, which obeys Hooke’s law, has an unstretched length of 10 cm.

A load of 20N is suspended from the spring. The new length of the spring is 36 cm.

What is the spring constant k of the spring?

• 0.56 N/ cm

• 0.77 N/ cm

• 1.3 N/ cm

• 1.8 N/ cm

A rocket is launched upwards from the surface of the Moon.

Hot gases are ejected downwards over a very short period of time.

Which statement is not correct?

• The rocket experiences a downward force.

• The rocket experiences an upward force.

• The total momentum of the hot gases is equal to the momentum of the rocket.

• The total momentum of the hot gases and rocket when the hot gases have been ejected is zero.

Electrical energy may be obtained from nuclear fission.

In which order is the energy transferred in this process?

• A nuclear fuel- generator- reactor and boiler - turbines

• A nuclear fuel -generator - reactor and boiler - turbines

• nuclear fuel -generator - turbines - reactor and boiler

• nuclear fuel - reactor and boiler -turbines -generator

A box of mass m slides down a slope of length l against a frictional force F. It descends a vertical height d. As the box slides down the slope, it loses gravitational potential energy and it does work against the friction.

Which row gives the loss in gravitational potential energy and the work done against friction?

• A

• B

• C

• D

A rope, connected to a pulley system and motor, is used to lift different objects through different distances. The time taken to lift each object is the same. The diagrams are not to scale.

Which motor requires the greatest power?

• A

• B

• C

• D