5 - Forces

Question 1

What is Acceleration?

Answer 1

The rate of change of velocity.

Question 2

What is Atmosphere?

Answer 2

The thin layer that surrounds the Earth

Question 3

How can Acceleration be calculated?

Answer 3

By using the gradient of a velocity-time graph.

Question 4

What happens to atmosphere as altitude increases?

Answer 4

Becomes less dense.

Question 5

What is Braking Distance?

Answer 5

The distance a vehicle travels under a braking force.

Question 6

What are some factors that affect Braking Distance?

Answer 6

• Road conditions.
• Weather Conditions.
• Vehicle Conditions (e.g. worn down brakes).

Question 7

What is the Centre of Mass?

Answer 7

The single point which the weight of an object is said to act.

Question 8

What is Displacement?

Answer 8

A measure of how far an object moves in a given direction.

Question 9

What is a Change of Momentum?

Answer 9

When a force acts on a moving object, or, a force act on a object that has the ability to move, a change in momentum will occur.

Question 10

What is the Conservation of Momentum?

Answer 10

The total momentum of a system before an event = Total momentum of a system after an event.

Question 11

What is a Contact Force?

Answer 11

A force that occurs only when objects physically touch.

Question 12

What is a Non-Contact Force?

Answer 12

A force that occurs only when objects do not touch physically.

Question 13

What is a Vector Quantity?

Answer 13

Quantities that have both Magnitude and Direction.
- Velocity is a Vector.

Question 14

What is a Scalar Quanitity?

Answer 14

Quantities that only have a Magnitude.
- Scalars only use a Scale.

Question 15

What is Thinking Distance?

Answer 15

The distance a vehicle has travelled in the time it takes for the driver to react.

Question 16

What factor can affect Thinking Distance?

Answer 16

• Tiredness.
• Alcohol use.
• Drug use.

Question 17

What is the equation for Stopping Distance?

Answer 17

Stopping Distance = Thinking Distance + Braking Distance

Question 18

What is a Moment?

Answer 18

The turning effect of a force.

Question 19

What is displacement?

Answer 19

Displacement is the distance an object moves on a straight line from a starting point to a finishing point and has a Magnitude and Direction.

Question 20

What is Force?

Answer 20

A push or pull on an object when it interact with another object.

Question 21

What is Friction?

Answer 21

When two surfaces touch and try to move against one another.

Question 22

Is displacement a vector or scalar quantity?

Answer 22

Vector.

Question 23

What Tension?

Answer 23

The pulling force that a string or cable exerts when something pulls on it.

Question 24

What is the area under a velocity-time graph equal to?

Answer 24

The distance an object has travelled.

Question 25

What is the equation for Speed?

Answer 25

Speed = Distance / Time

Question 26

What is the Equation for Acceleration?

Answer 26

Acceleration = change in velocity / Time taken

Question 27

What is Pressure?

Answer 27

Force per unit area.

Question 28

True or False. Air is lighter than water, therefore it does not exert pressure on the things beneath it.

Answer 28

False. It still exerts a pressure on the things beneath it.

Question 29

Why does pressure increase the deeper down you go in a swimming pool?

Answer 29

Because there is more water above you and therefore more weight, this weight exerts a larger force on your body.

Question 30

Where would atmospheric pressure be lowest: Top of Everest or Bottom of the Mariana Trench? Why?

Answer 30

Top of Everest, because there is less atmosphere above you and therefore less weight to push down on you.

Question 31

What is the Equation for Liquid Pressure?

Answer 31

The pressure beneath a liquids surface = Density of Fluid × Gravitational Field Strength × Depth

Question 32

What is Pressure measured in?

Answer 32

Pascals (Pa).

Question 33

What is Depth in the Context of a liquid?

Answer 33

The height of the column of liquid above a point.