1 1 movement and position

A distance-time graph shows the distance travelled by a moving object over a period of time.

On a distance time graph, constant speed is represented by a straight line:

On a distance-time graph, changing speed is represented by a curved line.

The equation used to find the gradient of a distance-time graph is Where:

On a distance-time graph, the line with the smallest gradient has the slowest speed. This is the shallowest line (the orange line).

True. A flat, horizontal line on a distance-time graph shows that the object is stationary. The distance the object has travelled is not changing with time.

The object in this distance-time graph has an increasing speed. The distance it travels in each interval of time is increasing; therefore, the line curves upward.

False. Speed is a scalar quantity because it only contains magnitude.

Average speed is the total distance moved divided by the total time taken.

The equation for calculating average speed is

Velocity describes both magnitude and direction of motion whereas speed describes only magnitude.

The difference between speed and velocity is that speed is a scalar, while velocity is a vector as it includes direction.

The total distance moved is calculated using the average speed by multiplying the average speed by the total time taken.

The units for speed are metres per second (m/s).

The journey took 100 seconds.

Acceleration is the rate of change of velocity.

Acceleration is measured in metres per second squared (m/s²).

The equation for average acceleration is
Where:

The equation for change in velocity is Where:

A positive acceleration indicates that the object is speeding up.

Negative acceleration indicates that the object is slowing down.

The acceleration of an object with constant velocity is zero.

The direction of acceleration is represented by a positive or negative value.

Deceleration is negative acceleration, it shows an object is slowing down.

A velocity-time graph shows how the velocity of a moving object varies with time.

Constant acceleration on a velocity-time graph is represented by a straight, sloping line.

False. A gentle slope on a velocity-time graph represents a small acceleration.

The velocity-time graph shows decreasing acceleration. The change in velocity per unit time decreases.

A flat, horizontal line indicates that the acceleration is zero, meaning the object is moving at a constant speed.

False. The starting velocity is not zero because the line does not start from the origin.

The area under a velocity-time graph represents the distance travelled by the object.

The total area under a velocity-time graph shows the total distance travelled. The total area is the sum of the areas of each enclosed section (triangle or rectangle).

The formula to calculate the area of a triangle is Where:

The formula to calculate the area of a rectangle is Where:

For an object with constant speed, the area under a velocity-time graph forms a rectangle.

The total distance travelled by the object in the velocity-time graph is 10 m.

The total distance travelled by the object in the velocity-time graph is 30 m.

Uniform acceleration is constant acceleration. The velocity changes by the same amount over each time interval.

The symbol for final speed is .

The units for final and initial speed are metres per second (m/s).

The symbol for initial speed is .

The symbol for distance moved is .

The equation for uniform acceleration is Where:

The equation for uniform acceleration when distance moved is the subject is Where: