exam type questions

Question 1

The hairdryer has a plastic case so there is no need for an earth wire connection in the plug.

Explain why the hairdryer is still safe to use.

Question 2

The tests were carried out on a dry road.
If the road is icy, describe and explain what change there would be, if any, to
(i) the thinking distance
(ii) the braking distance

Question 3

A student is investigating refraction of light.
(a) What is refraction?

Question 4

Explain how to produce a uniform magnetic field.

Question 5

The teacher makes a loud sound by hitting two cymbals together.
Each student starts a stopwatch when they see the teacher hit the cymbals. They
each stop their stopwatch when they hear the sound.
(a) Describe how a sound wave moves through the air.

Question 6

At first, the temperature of the water increases.
After a while, the temperature reaches a steady value below the boiling point of water.
Explain why the temperature reaches a steady value.

Question 7

Describe the advantages and disadvantages of series circuit when used as a heater in a car window.

Question 8

Explain why the acceleration is not constant, even though the engines produce a constant force.

Question 9

On a traditional cooker, a potato is placed in water in a pan on top of a hot plate.
Describe how energy is transferred from the hot plate to heat up all of the potato.

Question 10

A microwave cooker is often said to ‘cook the food from the inside’.
Explain whether this statement is true by describing how energy is transferred to
heat up all of the potato.

Question 11

In an induction cooker, there is a coil under the surface of the cooker.

A potato is placed in water in a metal pan.
An alternating current is switched on in the coil under the pan.
The coil does not heat the surface of the cooker.
Describe how energy is transferred to heat up all of the potato.

Question 12

The droplets of paint are given the same charge as they leave the sprayer.
Explain why this is an advantage.

Question 13

The droplets of paint are positively charged.
The object being painted is given a negative charge.
Explain why this is an advantage.

Question 14

Give one hazard caused by electrostatic charges and state how the risk from this hazard can be reduced.

Question 15

As he runs, the runner gets hot.
To avoid overheating, his body sweats.
As the sweat evaporates, it cools his body.
Use ideas about particles to explain why evaporation leads to cooling.

Question 16

At the end of a long race, runners are given a shiny foil sheet to wear.
This stops them cooling down too quickly.

(i) Suggest why a runner might cool down too quickly if he does not wear a foil sheet.

(ii) Explain how the foil sheet reduces heat loss.

Question 17

When the diver breathes out, bubbles are released.
Suggest why the bubbles expand as they rise to the surface.

Question 18

A student wants to investigate how the volume of a balloon changes with pressure.

(i) Suggest how the student could measure the volume of an inflated balloon.

Question 19

When the bicycle pump is used to inflate a tyre, the pump becomes hot.
Suggest why the pump becomes hot.