Paper 2 Forces

Question 1

What does a vector include?

Answer 1

Magnitude and Direction

Question 2

Give an example of a Vector

Answer 2

Velocity
Force
Acceleration

Question 3

What does a scalar include?

Answer 3

Magnitude

But NO direction

Question 4

Give an example of a scalar

Answer 4

Speed
Distance
Mass
Temperature
Time

Question 5

How is magnitude shown in a vector arrow?

Answer 5

The length of the arrow

Question 6

How is direction shown in a vector arrow?

Answer 6

Direction of the arrow

Question 7

What is the Weight equation?

Answer 7

Weight (N) = Mass (kg) x Gravity strength (N/kg)

Question 8

What is the gravitational field strength on earth?

Answer 8

9.8 N/kg

Question 9

What is a resultant force?

Answer 9

The overall force done on an object or point

Question 10

What is work done?

Answer 10

When a force moves an object through a distance, energy is transferred and work is done

Question 11

What is the Work done equation?

Answer 11

Work (J) = Force (N) x Distance (m)

Question 12

What is the Extension equation?

Answer 12

Extension (m) = Force (N) / Spring Constant (N/m)

Question 13

What is the Elastic potential energy equation?

Answer 13

EPE (J) = 1/2 x Spring Constant (N/m) x Extension^2 (m)

Question 14

What is the Moment equation?

Answer 14

Moment (Nm) = Force (N) x Distance (m)

Question 15

Where is the distance of a moment found?

Answer 15

The perpendicular distance from the pivot to the line of action of the force

Question 16

What is the Pressure equation (gases/liquids)?

Answer 16

Pressure (Pa) = Force (N) / Area (m^2)

Question 17

What is the pressure equation (just liquids)?

Answer 17

Pressure (Pa) = Depth (m) x Density (kg/m^3) x Gravity Strength (N/kg)

Question 18

What is upthrust? What is it equal to?

Answer 18

The force exerted on an object that has been submerged in a fluid

Force is equal to the weight of the object

Question 19

What is the speed equation?

Answer 19

Speed (m/s) = distance (m) / time (s)

Question 20

What is the acceleration equation?

Answer 20

Acceleration (m/s^2) = Change in velocity (m/s) / time (s)

Question 21

What is the velocity equation (including initial and final velocity)?

Answer 21

Final Velocity^2 (m/s^2) - Initial Velocity^2 (m/s^2) = 2 x Acceleration (m/s^2) x Distance (m)

Question 22

What is Newton’s first Law?

Answer 22

That a resultant force is needed to move an object

Question 23

What is Newton’s second law?

Answer 23

That acceleration is directly proportional to the resultant force

Question 24

What is Newton’s third law?

Answer 24

When two objects interact the forces are equal and opposite

Question 25

What is the resultant force equation?

Answer 25

Resultant force (N) = Acceleration (m/s^2) x Mass (kg)

Question 26

What is inertia?

Answer 26

An object’s resistance to its change in motion or speed?

Question 27

What is stopping distance?

Answer 27

The distance it takes to stop a car in an emergency

Question 28

What factors affect stopping distance?

Answer 28

• Thinking Distance - affected by speed and reaction time

- Braking Distance - affected by speed, road surface, tyres and brakes

Question 29

What is the equation for stopping distance?

Answer 29

Stopping distance = thinking + braking

Question 30

What is the momentum equation?

Answer 30

Momentum (kg m/s) = mass x velocity

Question 31

What is the equation for change in momentum?

Answer 31

Change (kg m/s) = Force (N) x Change in Time (s)

Question 32

Why are cars designed to increase time taken for a change in momentum?

Answer 32

So that less of a force is acted on the passengers and the injury is less severe.