IGCSE Edexcel Unit 2 Forces and Motion Double Award

average speed =

distance / time

Standard Unit for mass

kilogram (kg)

Standard Unit for distance or displacement

metre (m)

Standard Unit for speed or velocity

metre/second (m/s)

Standard Unit for acceleration

metre/second² (m/s²)

Standard Unit for gravitational field strength

Newton/kilogram (N/kg)

What does the gradient of a distance-time graph represent?

speed or velocity

What type of motion does a horizontal line on a distance-time graph represent?

stationary

Acceleration =

Change in velocity/time taken

What does the gradient of a velocity-time graph represent?

acceleration

What does the area under the line on a velocity-time graph represent?

Distance travelled

(final speed)² =

(initial speed)² + (2 x acceleration x distance)

What effect can a force have on an object?

It can change its speed, direction or shape

What is a vector quantity?

A measurement that has both magnitude and direction.

What is a scalar quantity?

A measurement with just magnitude (size).

Resultant Force is.....

The combination of all forces acting on an object.

Newton's 2nd Law: Resultant Force =

mass x acceleration

Weight =

mass x gravitational field strength

Friction and Air Resistance act in what direction?

The direction that opposes motion

What sort of motion is described by a curved line on a distance-time graph?

acceleration or deceleration

What sort of motion is described by a horizontal line on a velocity-time graph?

constant velocity

What does a steeper slope (larger gradient) on a velocity-time graph represent?

greater acceleration

What does a negative gradient (downwards slope) on a velocity-time graph represent?

deceleration

When do you get a zero resultant force?

When the forces on an object are balanced

Hooke´s Law states that:

the extension of an object is proportional to the force acting on it

What is displacement?

The distance travelled in a specific direction is called displacement.

What type of quality is displacement?

Displacement is a vector quality.

What is velocity?

Velocity is speed in a specified direction.

Is velocity scalar or vector?

Velocity is a vector quality.

Give the equation for acceleration.

acceleration = change in velocity / time taken

Is acceleration scalar or vector?

Acceleration is a vector.

How is constant velocity shown on a velocity-time graph?

Velocity-time graphs of objects moving with constant velocity are horizontal straight lines.

How is acceleration measured on a velocity-time graph?

The gradient of a velocity-time graph gives acceleration.

How is deceleration measured on a velocity-time graph?

A negative gradient (graph line sloping down to the right) indicates deceleration.

How can the the distance travelled be determined from a velocity-time graph?

The distance travelled can be worked out from the area under a velocity-time graph.

Give the equation for average velocity.

average velocity = initial velocity + final velocity / 2

Is speed scalar or vector?

Speed is scalar

Stopping distance is

Thinking distance + Braking distance

Braking distance is affected by

speed, mass, condition of tyres, condition of road

Thinking distance is affected by

visibility, tiredness, consumption of drugs

The relationship for weight is

mass x g

Terminal velocity is reached when

drag force balances the weight

Elastic behaviour is

The ability of a material to recover its original shape after the forces causing deformation have been removed.