Year 10 Physics

Question 1

Fully state Newton’s first law

Answer 1

Newton’s first law, also known as ‘inertia’, states that a moving object keeps moving unless acted upon by an external force. An object in rest stays in rest unless acted upon by an external force.

Question 2

An object is at rest. What does the object have that tends to keep it at rest?

Answer 2

Inertia = the tendency of an object to remain either in motion or at rest.
(Inertia is not a force)

Question 3

What would it take to force the object to move?

Answer 3

An unbalanced external force.

Question 4

According to Newton’s first law, there are 2 natural states of motion that an object tends to be in. What are they?

Answer 4

It will move at a constant speed, or rest.

Question 5

In real life, objects in motion don’t tend to stay in motion. What are 3 unbalanced forces that keep most objects that are in motion from remaining in motion indefinitely?

Answer 5

Friction, gravity and air resistance.

Question 6

What are 2 contact forces?

Answer 6

Push and pull

Question 7

What are 3 ‘field’ forces?

Answer 7

Gravitational, magnetic, electric.

Question 8

Describe ‘distance’, give an example

Answer 8

A scalar quantity that describes the measurement of length between 2 points; does not have a direction.
E.g) 10km to my house from here.

Question 9

Describe ‘displacement’.

Answer 9

A vector quantity that describes the overall change of position; has a direction.
E.g) 10km south to my house from here.

Question 10

Define ‘speed’ and state what unit it uses.

Answer 10

A scalar quantity (no direction) and measures how quickly an object is moving. Unit for speed is meters per second (m/s).

Question 11

Define ‘velocity’ and state what unit is used.

Answer 11

A vector quantity ( has direction) and is a measure of an object’s speed and direction. Units of velocity are metres per second (m/s).

Question 12

Define ‘acceleration’ and state what unit it uses. Include formular.

Answer 12

A vector quantity (has direction) rate of change of velocity and is measured with units meters per second squared (m/s^2).
Acceleration = change in speed/ changing in time.
= final speed - initial speed/ total time taken.

Question 13

Name 6 types of forces

Answer 13

Gravity, magnetic, electric, electromagnetic, friction and elastic.

Question 14

The acceleration of a free-falling object on earth is…
…and is called…

Answer 14

A free-falling object has an acceleration of 9.8 m/s/s, downward on Earth.
1 gravity (1g).

Question 15

What is air resistance

Answer 15

Friction between the air and a/the falling object. The opposing force to gravity.

Question 16

What is terminal velocity?

Answer 16

the constant speed that a freely falling object eventually reaches when the resistance of the medium through which it is falling prevents further acceleration.

Question 17

Fully state Newton’s second law.

Answer 17

F = m x a
An object will accelerate in the direction of an unbalanced force acting on it.
Size of acceleration depends on the object’s mass and size of the net fore acting upon it.

Question 18

Explain F (net) = m x a

Answer 18

f (net) - net force acting on the object - measured in newtons (N)
m = mass of object - measured in kg
a = acceleration of the object - measured in m/s^2
Equation can be arranged to find the mass and acceleration:
m = f/a
a = f/m

Question 19

Fully state Newton’s Third law

Answer 19

For every action force, there is an equal and opposite reaction force.
- when an object exerts a force on another object, the second object must exert another force back on the first one.
First objects - action force
Second object - reaction force.
They are both the same size and point in opposite directions.

Question 20

Explain ‘leaning on a wall’ using Newton’s third law.

Answer 20

When you lean on a wall, the wall pushes back with an equal force.