Forces

Question 1

What is a vector quantity

Answer 1

Quantity that has a direction and magnitude

Question 2

What is a scaler quantity

Answer 2

Quantity with only magnitude

Question 3

What are contact forces

Answer 3

When two objects have to be touching for the force act e.g. friction, a resistance, tension, normal contact force

Question 4

What are noncontact forces

Answer 4

When the objects do not need to be touching for the forced act e.g. magnetic force, gravitational force, electrostatic force

Question 5

What is the difference between weight and mass

Answer 5

Mass is just a matter of stuff on an object where is wait is the force acting on an object due to gravity

Question 6

What is Newton’s first law

Answer 6

If the resultant force on a stationary object is zero, the object will remain stationary or will carry on moving at the same velocity

Question 7

What are Free body diagram

Answer 7

They show all the forces acting on an object

Question 8

What Is resultant force

Answer 8

The overall force on a point or object

Question 9

What is distance

Answer 9

How far on objects move

– it is a scaler quantity and doesn’t involve direction

Question 10

What is displacement

Answer 10

Displacement is a vector quantity

– it measures distance and direction in a straight line from the object starting point to its finish point

Question 11

What is speed

Answer 11

Speed is just how fast are going with no direction

Question 12

What is velocity

Answer 12

velocity is speed given in a direction

Question 13

What is the equation for distance travelled

Answer 13

Speed (metres/seconds) X time (S)

Question 14

What are the typical everyday speeds for
– walking
– running
– cycling
-car
– train
– plane

Answer 14

Walking – 1.5 Metres per second
running –3 m/s
Cycling – 6 m/s
Car – 25 m/s
 train – 30 m/s
plane – 250 m/s

Question 15

What is acceleration

Answer 15

The change in velocity in a set amount of time

Question 16

What is Newton’s second law

Answer 16

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

Question 17

What is drag

Answer 17

The resistance you get in a fluid

Question 18

What is terminal velocity

Answer 18

This is when the resultant force is zero

– the frictional force is equal to the accelerating force

Question 19

What is friction

Answer 19

A force that acts in the opposite direction of movement

Question 20

What happens To drag as speed increases

Answer 20

Drag increases as speed increases

Question 21

Why must a car at a steady speed have a driving force

Answer 21

The driving force is cancelled out by the drag

Question 22

What affects terminal velocity

Answer 22

The less streamline the object is, the lower it’s terminal velocity (Object of large surface areas tend to have lower terminal velocity’s )
-This is because there is more a resistance acting on the object surface area

Question 23

Acceleration is proportional to the resultant force

Answer 23

Resultant force = mass X exhilaration

Question 24

What is Newton’s third law

Answer 24

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

Question 25

What ideas do Newton’s third law give

Answer 25

If you push something, it will push against you with the same force and as soon as you stop pushing so does it
– e.g. two skaters of different
mass: when they push off each other they feel opposite force In opposite directions and therefore Excelerator in different directions however as one has a smaller mass they will accelerate more

Question 26

What is thinking distance

Answer 26

Distance the car travels while different driver reacts to a hazard and starts to apply the brakes

Question 27

What Is breaking distance

Answer 27

The distance the car travels once the brakes have been applied and it comes to rest

Question 28

Factors can affect your thinking distance

Answer 28

Speed – the fast you’re going to further your travel during the time you take to react
– your reaction time – the longer your reaction time the lobby of thinking distance
– tiredness
– distraction
– drunkenness

Question 29

What are the factors that can affect your braking distance

Answer 29

Your speed – takes longer to break
– the weather or road surface-If it is wet or icy there is less group between the vehicles ties on the road
– conditions of tiredness –
– how good your brakes are – if they are 40 or worn they won’t be able to apply the force needed

Question 30

Where is the energy transfer when the car breaks

Answer 30

When a force is applied to the breaks of the vehicle, work done by the frictional force between the brakes and the wheel reduces the kinetic energy of the vehicle and the temperature of the brakes increases

Question 31

How do you check for reaction time

Answer 31

Ruler drop test

Question 32

What is the ruler drop test

Answer 32

One – sit with your arm resting on the edge of the table and get someone to hold a ruler so it hangs between your thumb and forefinger are lined with zero
Two-Without giving any warning the person holding the ruler to drop it and the other person should catch as quickly as possible
Three – the measurement on the ruler is the point where is court
Four – the longer the distance the longer reaction time
Five –

Question 33

What is the principle of conservation of momentum

Answer 33

Momentum is conserved in any collision or explosion provided no external factors or forces acts on the colliding or exploding bodies

Question 34

What happens to the extinction when the force is too large

Answer 34

The extension will reach its limit of proportionality

Question 35

Ching, compressing or bending transfers energy

Answer 35

When you apply a force on object you may cause it to stretch, compress or bend
-If an object has been elastically deformed it can go back to the original shape and length after it has been relieved of the force
– if an object has been inelastically deformed it can’t return to its original shape and length
– work is done when the force stretches or comprises of an object