P5 - Forces and their interactions

Question 1

What is a scalar quantity?

Answer 1

● A quantity that only has a magnitude

● A quantity that isn’t dependant on direction

Question 2

What is a vector quantity?

Answer 2

A quantity that has both a magnitude and an associated direction.

Question 3

How can a vector quantity be drawn and what does it show?

Answer 3

● As an arrow
● The length of the arrow represents the 
magnitude
● The arrow points in the associated 
direction

Question 4

What is a force?

Answer 4

A push or pull acting on an object due to an interaction with another object.

Question 5

What are the two categories that all

forces can be split into?

Answer 5

1. Contact forces (objects touching)

2. Non-contact forces (objects separated)

Question 6

Give three examples of contact forces.

Answer 6

1. Friction
2. Air resistance
3. Tension

Question 7

Give three examples of non-contact

forces.

Answer 7

1. Gravitational forces
2. Electrostatic forces
3. Magnetic forces

Question 8

Is force a vector or a scalar quantity?

Answer 8

● Vector
● It has both a magnitude and an
associated direction

Question 9

Give three examples of vector quantities.

Answer 9

1. Velocity
2. Displacement
3. Force

Question 10

Give three examples of scalar quantities.

Answer 10

● Temperature
● Time
● Mass
● Speed
● Distance 
● Energy

Question 11

What is weight?

Answer 11

The force that acts on an object due to gravity and the object’s mass.

Question 12

What quantities does weight depend on?

Answer 12

Weight = mass x gravitational field strength
● The object’s mass
● The gravitational field strength at the
given position in the field

Question 13

What is the unit used for weight?

Answer 13

The Newton (N).

Question 14

What is the unit used for gravitational

field strength?

Answer 14

N/kg

Question 15

What is meant by an object’s centre of

mass?

Answer 15

The single point where an object’s

weight can be considered to act through.

Question 16

What piece of equipment can be used to

measure an object’s weight?

Answer 16

A calibrated spring balance or newton meter.

Question 17

What is the name given to the single
force that is equivalent to all the other
forces acting on a given object?

Answer 17

The resultant force.