YEAR 7 REVISION QUESTIONS
Q1. The diagram shows a firework rocket.
(a) Three forces act as the rocket flies through the air. Which arrows show the directions of these
three forces?
A
(Thrust from the fuel combustion)
D
(air resistance - always in the opposite direction to travel)
E
(gravity)
3 marks
(b) When there is no fuel left, the rocket falls to the ground.
(i) Give the name of the force which pulls it down.
Gravity
(or weight of rocket)
1 mark
(ii) Give the name of the force which acts against the motion of the rocket.
Air resistance
1 mark
Maximum 5 marks
Q2.
Amr sits on a mat at the top of a helter-skelter and then slides down a chute around the outside.
(a)
(i)
Name two of the forces acting on Xander as he slides from point A to point B.
Gravity or weight
friction
Air resistance or 'drag'
2 marks
(ii) As Xander slides from point A to point B, the forces acting on him are balanced. Describe
Xander's speed when the forces acting on him are balanced.
constant speed
steady speed
it stays the same or it does not change
1 mark
(b) Xander goes back for a second go. This time he sits on a smooth cushion instead of a mat.
He goes much faster on the cushion. Give the reason for this.
A cushion is smoother than a mat. There will therefore be less friction
between the mat and the chute slide.
1 mark
(c)
On his third go Xander lies back on the cushion with his arms by his side.
What happens to his speed? Give the reason for your answer.
His speed will increase (he will go faster)
have less air resistance
because lying down he will
opposing his motion. He will be more
streamlined or aerodynamic.
Q3. The drawing below shows an astronaut in space.
He has four small jets attached to his space suit. These jets produce forces on the astronaut in the
directions A, B, C and D.
(a) The drawing below shows the size and direction of four forces acting on the astronaut. In
which direction, A, B, C or D, will the astronaut move?
The forces to left and right (D and B) cancel each other out.
The up force A is bigger than the down force C. There is therefore a net force of 1N upwards.
Answer: A
1 mark
(b) The drawing below shows the size and direction of four different forces acting on the
astronaut. Explain what will happen to the astronaut when the jets produce these four forces.
The forces to left and right (D and B) cancel each other out.
The up force A is the same as the down force C. There is therefore no
net force in the vertical direction.
There is no net force acting on him (the forces are balanced).
He will
therefore not accelerate.
He will continue to move at a steady speed in whatever direction he
had been travelling at the time the forces balanced.
That initial
speed might well have been zero, he would then continue to stay still.
'the forces are equal' is insufficient - must say the 'forces are equal and
opposite in direction'
2 marks
(c) The drawing below shows the size and direction of four different forces acting on the
astronaut. Draw an arrow on the diagram below to show the direction in which he will move.
See diagram
1 mark
Maximum 4 marks
Q 4: A bookshelf is 1 metre above the floor. As a book falls from the shelf to the floor it loses
7.5 J of potential energy.
(a)
(i) Select the correct statement about the kinetic energy of the book.



A
An object has gravitational potential energy by virtue of its position in the
gravitational field. The higher up it is, the more gravitational potential
energy it has.
An object has kinetic energy by virtue of its movement. The faster it goes
the more KE it has.
An objet moves faster as it falls.
While the book was resting on the shelf it had 7.5 J of kinetic
energy.
While the book was falling, its potential energy
B
was being transferred into kinetic energy.
C
While the book was falling its kinetic energy remained constant.
D
While the book was falling it lost kinetic energy.
1 mark
(ii) How much kinetic energy does the book have just before it hits the floor?
7.5 J
All of its GPE will have changed into KE just before it makes contact with the floor - it then gets
changed into heat and sound energy.
1 mark
(b) When the book hits the floor it stops and loses all its kinetic energy. What happens to this
energy?
It is transferred to the surroundings - into sound and heat energy.
1 mark
Maximum 3 marks
Q5: