P1&2. Measurements & Units, Forces & Motion

Question 1

Vector quantity

Answer 1

Magnitude and direction

Question 2

Scalar quantity

Answer 2

Magnitude only

Question 3

Zero error

Answer 3

An error in which an instrument gives a reading when the true reading at the time is zero

Question 4

Density

Answer 4

Mass per unit volume

Question 5

Speed

Answer 5

Rate of change in distance

Question 6

Velocity

Answer 6

Rate of change in displacement

Question 7

Acceleration

Answer 7

Rate of change in velocity

Question 8

Thinking distance

Answer 8

Distance travelled in between the driver realising he needs to brake and pressing the brakes

Question 9

Braking distance

Answer 9

Distance taken to stop once the brakes are applied

Question 10

Mass

Answer 10

The amount of matter contained in an object

Question 11

Weight (gravitational force)

Answer 11

Gravitational pull on an object

Question 12

Law of Inertia

Answer 12

A body in motion stays in motion and a body at rest stays at rest unless acted on by an unbalanced force

Question 13

Newton’s 2nd Law

Answer 13

Acceleration is directly proportional to the force and inversely proportional to the mass of the object

Question 14

Newton’s 3rd Law

Answer 14

To every action there is an equal in magnitude but opposite in direction reaction

Question 15

Inertia

Answer 15

Tendency of an object to resist change

Question 16

Momentum

Answer 16

Measure of inertia

Question 17

Principle of Conservation of Momentum

Answer 17

The momentum before collision is equal to the momentum after collision in a closed system (no friction)

Question 18

Centripetal force

Answer 18

The force that pulls objects towards the axis of rotation during circular motion