Calculating from displacement-time graphs: including tangents (v=x/t) | Starter Quiz | Oak National Academy

Which of the following are features of a typical displacement–time graph?

• time is shown on the x–axis (horizontal)

• time is shown on the y–axis (vertical)

• displacement is shown on the x–axis (horizontal)

• displacement is shown on the y–axis (vertical)

Answer explanation

A displacement–time graph should have time on the x-axis and displacement on the y-axis.

Match the quantity to the correct description.

• displacement

• a scalar measured in m/s

• distance

• a scalar measured in m

• speed

• a vector measured in m

• velocity

• a vector measured in m/s

Answer explanation

Displacement (vector) is distance (scalar) moved, but in one particular direction. Velocity is how quickly an object moves in a particular direction (vector), and speed is just how quickly an object moves (scalar).

Which of the following are examples of velocity?

• 4 km north

• 3 km/s

• 12 m/s upwards

• 2 mph west

• 100 km/h

Answer explanation

Velocity is how quickly an object moves in a particular direction, so 12 m/s upwards and 2 mph west are velocities. 4 km north is a displacement and 3 km/s and 100 km/h are speeds.

Which of the following features of a displacement–time graph indicates an object travelling at the greatest speed?

• The time will be at its maximum value.

• The displacement will be at its maximum value.

• The gradient of the line will be the steepest.

• The gradient of the line will be the shallowest.

• The gradient will be zero (flat).

Answer explanation

The greatest speed is shown by the steepest gradient.

Calculate the speed of a car that travels 500 m in 25 s. Include the unit in your answer.

Answer explanation

The speed can be found using the equation: speed = distance ÷ time so speed = 500 m ÷ 25 s = 20 m/s.

How long will a fish travelling at 2.5 m/s take to travel 1.5 km?

• 0.6 minutes

• 1 minutes

• 3.75 minutes

• 10 minutes

• 5 minutes

Answer explanation

time = distance ÷ speed = 1500 m ÷ 2.5 m/s = 600 s = 10 minutes