7K — Forces

Question 1

What is the unit for measuring:

1) Force
2) Mass
3) Weight

Answer 1

1) Newtons (N)
2) Kilograms (Kg)
3) Newtons (N)

Question 2

1) Define mass.

2) Define weight.

Answer 2

1) Mass is the amount of matter that something is made from.

2) Weight is the amount of force with which gravity pulls things.

Question 3

What is a force?

Answer 3

A force is a push or pull.

Question 4

What is friction?

Answer 4

Friction is a force caused by two things rubbing together.

Question 5

1) What is a contact force?

2) What is a non-contact force?

Answer 5

1) A contact force is a force that only acts when two objects are touching.
2) A non-contact force is a force that can have an effect without objects touching.

Question 6

What happens when a force is applied to an elastic material?

Answer 6

Elastic materials will stretch with a force and then return to their original shape when the force is taken away.

Question 7

1) What is Hooke’s Law?

2) What is an elastic limit?

Answer 7

1) Hooke’s Law is the law that says the extension of a spring is proportional to the force on it.
2) The elastic limit is how far a spring can be stretched before it is permanently stretched and no longer elastic.

Question 8

1) Examples of contact forces

2) Examples of non-contact forces

Answer 8

1) — Friction
— Air resistance
— Water resistance
— Upthrust
2) — Magnetism
— Gravity
— Static electricity