Exam qs

Question 1

The miners working in a salt mine use smooth wooden slides to move quickly from one level to another.
The speed of the miner at the bottom of the slide is much less than the calculated maximum possible speed.
Explain why.

Answer 1

• work done against resistive forces (e.g. friction, air resistance)
• causing kinetic energy to be transferred as heat to the surroundings

Question 2

Some people heat their homes using electric heaters. Others heat their homes using a wood burning stove.
Give two environmental advantages of using a wood burning stove to heat a home rather than heaters that use electricity generated from fossil fuels.

Answer 2

1. No fossil fuels burnt
2. Renewable energy resource

Question 3

What happens to an electric field if the charge increases?

Answer 3

When an electric field increases its charge gets larger / increases / there is more electric force / is more powerful

Question 4

The Titanic ship in 1912 sank in the North Atlantic. Describe the forces acting on the ship to cause it to sink.

Answer 4

• Weight acting downwards
• Normal force acting upwards
• Weight was larger than normal force to cause it to sink

Question 5

Determine the mass of an object if an object’s weight is 81N and the gravitational field strength is 9.5N/kg.
Give your answer to 3 significant figures

Answer 5

Weight = Mass x gravitational field strength
Weight = 81N
Gravitational field strength = 9.5N/kg
81 = mass x 9.5
81/9.5 = 8.526316
m = 8.53kg

Question 6

A student replaces a moving coil ammeter with a digital ammeter
The digital ammeter has a higher resolution than the moving coil ammeter.
Give one other reason why it would be better to use a digital ammeter throughout an investigation.

Answer 6

It would have given more precise readings- gives a reading closer to the true value

Question 7

Explain one environmental effect of generating electricity using a gas-fired power station

Answer 7

Releases carbon dioxide which causes global warming

Question 8

Fine powders poured through a pipe can become charged
In industry, powders are often pumped through pipes. If the static charge caused a spark, the powder could ignite and cause an explosion.
Suggest one way the risk of an explosion could be reduced

Answer 8

Earth the pipe