Forces and Motion - Paper 2

Question 1

What is the difference between distance and displacement?

Answer 1

Distance is a scalar quantity representing how far an object moves.
Displacement is a vector quantity representing the length and direction of the straight path between the start and end points.

Question 2

Give a typical walking speed

Answer 2

1.5 m/s

Question 3

Give a typical running speed

Answer 3

3 m/s

Question 4

Give a typical cycling speed

Answer 4

6 m/s

Question 5

Give the typical speed of sound in air

Answer 5

330 m/s

Question 6

Define velocity

Answer 6

The velocity of an object is its speed in a certain direction.

Question 7

Describe terminal velocity

Answer 7

An object falling through a fluid initially accelerates due to the force of gravity. As the object’s velocity increases, the drag force acting on it increases. Eventually the resultant force will be zero and the object will move at its terminal velocity.

Question 8

What is Newton’s first law of motion?

Answer 8

If the resultant force acting on an object is zero and the object is stationary, the object remains stationary.
If the resultant force acting on an object is zero and the object is moving, the object continues to move at the same velocity.

Question 9

Define inertia

Answer 9

Inertia is the tendency of objects to continue in their state of rest or of uniform motion.

Question 10

What is Newton’s second law of motion?

Answer 10

The acceleration of an object is proportional to the resultant force acting on the object, and inversely proportional to the mass of the object.

Question 11

Define inertial mass

Answer 11

Inertial mass is a measure of how difficult it is to change the velocity of an object, defined as the ratio of force over acceleration.

Question 12

What is Newton’s third law of motion?

Answer 12

Whenever two objects interact, the forces they exert on each other are equal and opposite.

Question 13

Define stopping distance

Answer 13

The stopping distance of a vehicle is the sum of the distance the vehicle travels during the driver’s reaction time (thinking distance) and the distance it travels under the braking force (braking distance).

Question 14

What factors affect the braking distance of a vehicle?

Answer 14

Adverse road conditions, including wet or icy conditions.
Poor condition of the vehicle, limited to the vehicle’s brakes or tyres.