O-Level Combined Science — Physics 2

Question 1

Which of the following is a good conductor of electricity?

Accepted Answer

Copper

Answer

Copper is an excellent conductor of electricity due to its free electrons that can move easily.

Question 2

What happens to the resistance of a wire if its length is doubled?

Accepted Answer

Doubled

Answer

Resistance is directly proportional to length (R = ρL/A). Doubling the length doubles the resistance.

Question 3

A wave has frequency 50 Hz and wavelength 4 m. What is its speed?

Accepted Answer

200 m/s

Answer

Wave speed = frequency × wavelength = 50 × 4 = 200 m/s.

Question 4

What is the principle of conservation of energy?

Accepted Answer

Energy cannot be created or destroyed, only converted

Answer

The principle of conservation of energy states that energy cannot be created or destroyed, only converted from one form to another.

Question 5

Which colour of visible light has the highest frequency?

Accepted Answer

Violet

Answer

In the visible spectrum, violet light has the highest frequency (and shortest wavelength), while red has the lowest frequency.

GCE O-Level Practice Test