2. Page 81, exercise 3. Finish the sentence.
1. Contact forces require …
2. A contact force can be a push force or …
3. Contact forces can be applied by people, animals and…
4. Kicking a ball is an example of a contact force causing…
5. To lift a car you need a machine called …
6. A footballer applies contact forces to the ball using his…
7. A contact force applied to plasticine changes its …
8. A medium contact force applied to an egg causes it to…
3. Page 83, exercise 4. Answer true or false.
1. Magnets create magnetic forces.
2. Magnetic forces are contact forces.
3. Magnetite is a mineral that is a natural magnet.
4. Both ends of a magnet are exactly the same.
5. Magnets attract all metal objects.
6. Magnets attract or repel each other.
7. The north pole of a magnet and the south pole of another
magnet repel each other.
8. The south poles of 2 magnets repel each other.
4. Page 85, exercise 4. Answer the questions.
1. Is gravity a contact force or a non-contact force?
2. On the Earth, does gravity pull objects towards its centre or towards
space?
3. Which has a bigger mass: the Earth or the Moon?
4. Which has more gravity: the Moon or the Earth?
5. Where can you jump higher: on the Earth or on the Moon?
6. Where does a sack of potatoes feel heavier: on the Earth or on the
Moon?
7. Where is there least gravity: on the Earth, on the Moon or in space?
8. Why do apples fall off trees: because of gravity or magnetic forces?
6. Page 81, exercise 3. Finish the sentence.
1. Contact forces require … (touch).
2. A contact force can be a push force or … (a pull force).
3. Contact forces can be applied by people, animals and…(machines).
4. Kicking a ball is an example of a contact force causing…(movement).
5. To lift a car you need a machine called … (a crane).
6. A footballer applies contact forces to the ball using his…(feet and
head).
7. A contact force applied to plasticine changes its …(shape).
8. A medium contact force applied to an egg causes it to…(break).
7. Page 83, exercise 4. Answer true or false.
1. Magnets create magnetic forces. (True.)
2. Magnetic forces are contact forces. (False.)
3. Magnetite is a mineral that is a natural magnet. (True.)
4. Both ends of a magnet are exactly the same. (False.)
5. Magnets attract all metal objects. (False.)
6. Magnets attract or repel each other. (True.)
7. The north pole of a magnet and the south pole of another
magnet repel each other. (False.)
8. The south poles of 2 magnets repel each other. (True.)
8. Page 85, exercise 4. Answer the questions.
1. Is gravity a contact force or a non-contact force? (A non-contact force.)
2. On the Earth, does gravity pull objects towards its centre or towards space?
(Towards its centre.)
3. Which has a bigger mass: the Earth or the Moon? (The Earth.)
4. Which has more gravity: the Moon or the Earth? (The Earth.)
5. Where can you jump higher: on the Earth or on the Moon? (On the Moon.)
6. Where does a sack of potatoes feel heavier: on the Earth or on the Moon? (On
the Earth.)
7. Where is there least gravity: on the Earth, on the Moon or in space? (In space.)
8. Why do apples fall off trees: because of gravity or magnetic forces? (Gravity.)
