Forces and Movement

Question 1

Equation for Average speed

Answer 1

Average speed= distance moved/time taken

Question 2

On a graph if an object is moving in a straight line but sloped, what does that mean?

Answer 2

Constant speed

Question 3

What is the force that acts between two masses?

Answer 3

Weight or Gravity

Question 4

When an object is stationary, what does that mean on a distance time graph?

Answer 4

It’s is horizontal.

Question 5

What is the equation for acceleration?

Answer 5

Acceleration(m/s2)= change in velocity(m/s) / time taken(s)

(a=(v-u) / t

Question 6

What happens to an object when it is moving at constant velocity in a velocity time graph?

Answer 6

The line is straight in other words horizontal.

Question 7

When an object is at zero in a velocity time graph what is happening?

Answer 7

The object is at rest.

Question 8

When the line is steeper on a velocity time graph, what does that mean?

Answer 8

The steeper the line, the greater the acceleration.

Question 9

What’s the equation for force?

Answer 9

Force= Mass x Acceleration

Question 10

What is friction?

Answer 10

Friction is a force that opposed motion. For example, the bigger the forces to pull the block, the higher the friction.

Question 11

What happens to the resultant force if it’s at zero?

What happens to the resultant force if it’s NOT zero?

Answer 11

The moving object will stay at the same speed.

The moving object will slow down depending on the direction of the resultant force.

Question 12

Equation for Weight

Answer 12

Weight(N)= mass(kg) x gravitational field strength(N/kg)

Question 13

Three stages of falling.

Answer 13

1. The object accelerates downwards because of its weight and the resultant force is acting downwards.
2. The air resistance increases.
3. Eventually the object’s weight balances by the air resistance and this is know as Terminal Velocity.

Question 14

Factors affecting terminal velocity.

Answer 14

1. Mass
2. Surface area
3. The acceleration due to gravity, g.

Question 15

Equation for stopping distance.

Answer 15

Stopping distance= thinking distance + braking distance

Question 16

Factors of thinking distance

Answer 16

1. Tired
2. Distracted
3. Under the influence of alcohol and drugs

Question 17

Factors of Braking distance

Answer 17

1. Tyres are in poor condition or the car’s brakes.
2. The poor road or weather conditions( e.g. Icy roads or wet roads)
3. The car has a larger mass( e.g. More people)

Question 18

What happens when the brakes are applied in a car?

Answer 18

Work is down by the frictional force which reduces the kinetic energy of the car and it increases the temperature of the brakes.

Question 19

Equation for momentum.

Answer 19

Momentum(kg m/s)= mass(kg) x velocity(m/s)

P= m x v

Question 20

Equation for force involving momentum.

Answer 20

Force(N)= Change in momentum(kg m/s) / time