P1 2022 5105

Which statement about all physical quantities is correct?

• They have a magnitude and a unit but not all have a direction.

• They have a magnitude and a direction but not all have a unit.

• They have a unit and a direction but not all have a magnitude.

• They have a magnitude, a unit and a direction.

Answer explanation

The correct statement is that all physical quantities have a magnitude and a unit, but not all have a direction. For example, mass and temperature have magnitude and unit, but no direction.

Which graph represents the motion of an object that is dropped from rest and falls 45 m?

• A

• B

• C

• D

Answer explanation

Graph C represents the motion of an object dropped from rest, showing a parabolic curve that indicates increasing speed as it falls 45 m due to gravity. The other graphs do not accurately depict this motion.

A child sits on a rubber ball and bounces up and down on the ground. What stays the same when the ball hits the ground?

• the acceleration of the ball

• the mass of the ball

• the shape of the ball

• the velocity of the ball

Answer explanation

The mass of the ball remains constant regardless of its motion or shape changes during bouncing. Other factors like acceleration and velocity change when the ball hits the ground.

A rocket has a mass of 16000kg.

When it is on the Moon it experiences the Moon's gravitational field strength of 1.6N/kg.

What is the weight of the rocket on the Moon?

• 1000 N

• 2560 N

• 10 000 N

• 25 600 N

Answer explanation

Weight is calculated using the formula: Weight = mass × gravitational field strength. Here, Weight = 16000 kg × 1.6 N/kg = 25600 N. Therefore, the weight of the rocket on the Moon is 25600 N.

How is pressure calculated?

• A

• B

• C

• D

Answer explanation

Pressure is calculated using the formula P = F/A, where P is pressure, F is the force applied, and A is the area over which the force is distributed. Therefore, the correct choice is A.

A man with his ankles tied to an elastic rope steps off a bridge. During the fall, his gravitational

potential energy is converted at various stages to kinetic energy, elastic potential energy in the

elastic rope and thermal energy due to air resistance.

At his lowest position the man is at rest and he has lost 30000J of gravitational potential energy. Thermal energy of 1000J has been produced.

Which row shows values for the kinetic energy and the elastic potential energy at the lowest

position the man reaches?

• A

• B

• C

• D

Answer explanation

At the lowest position, the total energy lost is 30000J (gravitational potential) minus 1000J (thermal), leaving 29000J. Since the man is at rest, kinetic energy is 0J, so elastic potential energy is 29000J. Thus, the correct choice is B.

What is a form of energy?

• friction

• voltage

• temperature

• light

Answer explanation

Light is a form of energy that is visible to the human eye, while friction, voltage, and temperature are not forms of energy themselves but rather effects or measurements related to energy.

During a change of state, molecules continue to move at random throughout a substance and the force between the molecules increases.

What is this change of state?

• from gas to liquid

• from liquid to gas

• from liquid to solid

• from solid to liquid

Answer explanation

The change of state from gas to liquid involves molecules moving randomly while the forces between them increase as they come closer together, leading to condensation.

A thermometer is placed in a beaker of a liquid substance. Its temperature is recorded as 10 °C.

The substance is cooled to -10 °C and the readings on the thermometer are recorded at regular

intervals.

A graph of temperature against time is shown. Which parts of the graph represent when the thermometer is losing thermal energy to the surrounding substance?

• R and S only

• R and T only

• S and T only

• R, S, and T

Answer explanation

The thermometer loses thermal energy when its temperature decreases. In the graph, segments R and T show a decline in temperature, indicating heat loss to the surrounding substance, while S shows a steady temperature.

Waves are made in a ripple tank.

What is transferred by the waves?

• energy

• frequency

• mass

• wavelength

Answer explanation

Waves in a ripple tank transfer energy through the medium, causing particles to oscillate. While frequency and wavelength describe wave properties, they do not represent what is transferred by the waves.