Scalar and vector quantities

Ice hockey is a team sport played on ice. Players try to hit a disc called a puck into the other team’s goal.

(Source: © Alexandr Grant / Shutterstock)

Diagram 1 shows a puck travelling across some smooth ice.

State the formula linking average speed, distance moved and time taken.

The puck travels at a constant speed of 2.8 m/s.

Calculate the distance moved by the puck in a time of 3.5 s.

Diagram 2 shows a puck travelling across some rough ice.

The rough ice exerts a frictional force on the puck.

Draw a labelled arrow on diagram 2 to show the force of friction acting on the puck.

Explain how the force of friction changes the velocity of the puck.

The boxes show some physical quantities and their units.

Draw a straight line from each physical quantity to its correct unit.

One has been done for you.

Physical quantity
Unit

Some physical quantities are scalars and other physical quantities are vectors.

State the difference between a scalar quantity and a vector quantity.

Give an example of a scalar quantity.

The diagram shows a child on a zip-line ride.

During the ride the child slides along a metal wire with the velocity in the direction shown in the diagram.

The diagram also shows the tension force acting on the safety harness the child is wearing.

Force and velocity are examples of vector quantities.

State what is meant by the term vector quantity.

Draw labelled arrows on the diagram to show two other forces that act on the child.

This question is about scalar quantities and vector quantities.

Give a similarity and a difference for scalar quantities and vector quantities.

similarity

difference

The box gives some physical quantities.

Draw a circle around each physical quantity that is a scalar.

The diagram shows four forces acting on an object.

Calculate the size and direction of the resultant force.

A ship floats on the sea.

The ship floats because of the forces acting on it.

The upward force acting on the ship is called upthrust.

This force is shown on the diagram.

Draw another labelled arrow on the diagram to show the other vertical force acting on the ship.

Forces are vector quantities.

State what is meant by the term vector quantity.

Give another example of a vector quantity.

The upthrust force acting on the ship is proportional to the pressure difference between the bottom of the ship and the surface of the sea.

The pressure acting on the ship at the surface of the sea is 100 kPa.

State the formula linking pressure difference, height, density and gravitational field strength (g).

The bottom of the ship is 15.8 m below the surface of the sea.

Show that the pressure acting on the bottom of the ship is approximately 260 kPa.

[density of seawater = 1030 kg/m³]

Explain why the bottom of the ship is deeper below the surface of the sea when the ship is fully loaded with cargo.