4.7.1 Forces and Motion

Question 1

What is Displacement?

Answer 1

The straight line distance between a start and end point

Question 2

What type of quantity is distance?

Answer 2

Scalar

Question 3

Define a vector quantity.

Answer 3

A quantity with magnitude and direction.

Question 4

How do you calculate speed?

Answer 4

Speed = Distance/Time

Question 5

What does a straight diagonal line show on a DT graph?

Answer 5

Constant Speed

Question 6

What does the area under a VT graph show?

Answer 6

Distance Travelled

Question 7

What is typical walking speed?

Answer 7

1.5 m/s

Question 8

What is typical running speed?

Answer 8

3 m/s

Question 9

What is typical cycling speed?

Answer 9

6 m/s

Question 10

How would you describe the velocity of an object in circular motion?

Answer 10

Velocity of an object in circular motion is constantly changing

Question 11

What three things does the size of centripetal force depend on?

Answer 11

Speed, Mass, Radius of Circle

Question 12

What are the units of acceleration?

Answer 12

m/s^2

Question 13

What does a straight diagonal line show on a VT graph?

Answer 13

Constant acceleration

Question 14

What is Newton’s First Law?

Answer 14

If the resultant force on an object is zero, it will continue to move in the same direction at the same velocity

Question 15

What is Newton’s Second Law?

Answer 15

Acceleration is proportional to the resultant force acting on an object, and is inversely proportional to mass.

Question 16

What is Newton’s Third Law?

Answer 16

Every action force has an equal and opposite reaction force

Question 17

What is the equation for Kinetic Energy?

Answer 17

KE = 0.5 x mass x velocity^2

Question 18

What is Inertia?

Answer 18

The tendency of object to continue in their state of rest or of uniform motion

Question 19

What is the equation for Momentum?

Answer 19

Momentum(p) = mass(m) x velocity(v)

Question 20

What is the law of Conservation of Momentum?

Answer 20

In a closed system, the total momentum before an event is equal to the total momentum after the event

Question 21

How is Stopping Distance calculated?

Answer 21

Braking distance + Thinking Distance

Question 22

What factors can affect thinking distance?

Answer 22

Tiredness, Drugs, Alcohol, Distractions

Question 23

What factors can affect Braking distance?

Answer 23

Wet or Icy weather, poor road conditions, poor car conditions

Question 24

How is the relationship between velocity and stopping distance?

Answer 24

As velocity increases so does braking distance

Question 25

What energy transfer occurs when a car brakes?

Answer 25

Kinetic energy -> Thermal Energy

Question 26

What does the gradient of a DT graph show?

Answer 26

Speed

Question 27

How is the gradient of a curved line of best fit calculated at a specific point?

Answer 27

A tangent is drawn and the gradient is calculated

Question 28

How does Centripetal force act on an object?

Answer 28

Centripetal force acts inwards

Question 29

What is air resistance?

Answer 29

A force of friction produced when an object moves through the air

Question 30

How is change in velocity calculated?

Answer 30

Change in Velocity = Final Velocity - Starting Velocity

Question 31

State the equation linking Change in velocity, acceleration and distance.

Answer 31

Change in Velocity^2 = 2 x Acceleration x Distance

Question 32

What does a negative change in velocity show?

Answer 32

Deceleration

Question 33

What is terminal velocity?

Answer 33

The maximum speed of an object travelling

Question 34

Describe the forces acting on an object at terminal velocity.

Answer 34

The forces are balanced

Question 35

Identify the main energy transfer of an object as it falls.

Answer 35

Gravitational potential energy -> Kinetic Energy

Question 36

How does a parachute decrease terminal velocity?

Answer 36

The parachute increases air resistance, causing deceleration. When the forces become balanced, the terminal velocity is lower

Question 37

Identify the Gravitational Field Strength of Earth.

Answer 37

9.8 N/kg

Question 38

What force prevents an apple from falling to the ground?

Answer 38

Tension of the stalk

Question 39

According to Newton's 1st, what is needed to make an object accelerate?

Answer 39

An overall resultant force applied to the object

Question 40

Identify the equation linking Force, mass and acceleration.

Answer 40

Force = Mass x Acceleration

Question 41

How can acceleration be measured more accurately?

Answer 41

Using a light gate to reduce random error from human measurement

Question 42

If a ball impacts a solid desk with 10N of force, how much force is exerted on the ball?

Answer 42

10N (Newton's 3rd Law)

Question 43

Identify the range of average human reaction time.

Answer 43

0.3 - 0.9s

Question 44

What two forces are acting on a falling object?

Answer 44

Weight/Gravity, Air resistance

Question 45

In what direction does centripetal force act?

Answer 45

Inwards

Question 46

True or false: Centripetal force can only be supplied by a contact force.

Answer 46

False: This can be a contact or Non-contact force i.e Gravity

Question 47

How would a stationary object look on a DT graph?

Answer 47

Flat line

Question 48

What does a flat line show on a VT graph?

Answer 48

Constant speed

Question 49

How are acceleration and mass related?

Answer 49

Acceleration is inversely proportional to mass

Question 50

What are the units of kinetic energy?

Answer 50

Joules (J)