A stable well-designed racing car must have

• low centre of gravity

• narrow wheel base

• long front

• double exhausts

Which of the following a scalar quantity?

• Energy

• Acceleration

• Velocity

• Weight

An object is removed from the ground and placed on a shelf. Which of its properties would you expect to change?

• Mass

• Volume

• Potential Energy

• Kinetic Energy

Coal is sometimes burnt in order to drive steam engines. Which of the following is the sequence of energy changes involved in the activity?

• chemical to kinetic to electrical

• chemical to heat to kinetic

• kinetic to electrical to chemical

• chemical to kinetic to heat

What is the gain in gravitational potential energy of a body of weight 2000N as it rises from a height of 20 m to a height of 25m above the earth's surface?

• 400 J

• 1000 J

• 10 000 J

• 20 000 J

The periodic time of a simple pendulum can be increased by

• increasing the length of the cord

• decreasing the length of the cord

• increasing the mass of the bob

• decreasing the amplitude of oscillation

The relative density of brass is 8.4.

Which of the following is the best statement that can be made?

• Brass is heavier than water

• Water is heavier than brass

• 100 cm^3 of brass is heavier than 100 cm^3 of water

• 100 cm^3 of water is heavier than 100 cm^3 of brass

The diagram shows a Force-extension graph for a light spring.

Which of the following statements would be true?

I- The elastic limit of the spring was exceeded

II- The spring obeyed Hooke's Law over its entire extension

III- The force per unit extension in the elastic region was 7.5 Ncm^-1.

• I only

• I and II only

• I and III only

• I, II and III

What is the mass of a woman of weight 700 N? (g=10 N/kg)

• 70 kg

• 700 kg

• 7 000 kg

• 70 000 kg

Which of the following best describes the graph of force against extension for a spring?

• a straight line with an intercept on the y axis

• a straight line through the origin

• a straight line through the origin, up to a limit of proportionality

• an upward curve that passes through the origin