Motion, forces

Question 1

Difference between vector and scalar quantities

Answer 1

Vector quantities have magnitude and direction

Scalar quanties only have magnitude

Question 2

What is the difference between distance and displacement?

Answer 2

Distance is just how far an object has moved (Scalar so no direction)

Displacement is the distance and direction in a straight line from the start to the end point

Question 3

Example of distance and displacement

Answer 3

Distance - 30m
Displacement - 5 metres north
If you walk 5m north, then 5m south your displacement is 0 but distance travelled is 10m

Question 4

Difference between speed and velocity

Answer 4

Speed is how fast your going (30mph) with no reguard of direction
Velocity is speed in a given direction (30mph north)

Question 5

Scalar Quantities

Answer 5

Speed, distance, mass, time, temperature, energy

Question 6

Vector quantities

Answer 6

Force, displacement, velocity, weight, acceleration, momentum

Question 7

Equation for speed and velocity

Answer 7

Speed = distance ÷ time

Velocity = displacement ÷ time

The units will change (velocity) will inculude a direction

Question 8

What axis is time on

Answer 8

x

Question 9

What does acceleration mean?

Answer 9

Change in velocity in a certain amount of time

Question 10

Equation for acceleration

Equation for constant acceleration

Answer 10

A = (v-u) / t

V² - u² = 2 x a x z

A is acceleration Z is distance

Question 11

What happens to acceleration in a circle?

Answer 11

If an object moves at a constant speed in a circle then it’s velocity is constanly changing even though it’s speed is constant.

Question 12

How to calculate distance on a velocity time graph

Answer 12

Finding triangles and squares and then adding the area up

Question 13

What is newtons first law?

Answer 13

If the resultant force on a stationary object is zero, the object will remain stationary. If the resultant force on a moving object is zero, it’ll just carry on moving at the same velocity

Question 14

What does a resultant force do?

Answer 14

It makes something stop moving, change direction, slow down and speed up

Velocity will stay the same

Question 15

What is newtons second law?

Answer 15

F = m x a

Question 16

What does newtons second law tell us?

Answer 16

The acceleration of an object is inversely proportional to the mass of the object

Question 17

What is the difference between mass and weight?

Answer 17

Mass is the amount of stuff/matter. For any object it’s value will stay the same anywhere in the universe.

Weight is the force acting on an object due to gravity pulling it towards the earth
Direction downwards

Mass is scalar and Weight is vecor

Question 18

Equations to measure weight

Answer 18

Weight = mass (kg) x gravitaional field strenghth (n/kg)

Question 19

Investigate the motion of a trollry on a ramp

Question 20

What does inertia mean?

Answer 20

Inertia is the tendency for motion to remain unchanged

Question 21

What is newtons third law ?

Answer 21

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

Question 22

What is a centripetal force?

Answer 22

A force that acts towards the center of a circle
If an object is travelling in a circle it is constantly changing direction so constantly changing velocity meaing it’s accelerating

Question 23

Examples of centripetal forcses

Answer 23

Gravity (statlights)
Friction (A car turning)
Tension (holding on to a roundabout)

Question 24

Stopping distance

And eqaution

Answer 24

The distance covered between the driver first spotting a hazard and the vehicle coming to a stop

Stopping distance = thinking distance + braking distance

Question 25

What is thinking distance?

Answer 25

Thinking distance is the distance the car travels in the driver's reaction time (the time between noticing the hazard and applying the brakes)

Question 26

What is braking distance?

Answer 26

The braking distance is the distance taken to stop once the brakes have been applied

Question 27

Factor affecting braking distance

Answer 27

1. Your speed - the faster your going the longer it takes to stop 2. The mass of the car- a car full of people and luggage won't stop as quick as an empty one 3. The condition of the brakes - worn or faulty ones won't be able to brake with as much force 4. How much friction is between your tyres and the road (your more likely to skid on dirty, wet or icy roads)

Question 28

Factors affecting thinking distance

Answer 28

1. Your reaction time - this is increased by tiredness, alcohol, drugs and distractions 2. Your speed - the faster you're going, the further you'll travel during your reaction time

Question 29

What does more friction do ?

Answer 29

The more friction there is between the tyre and the road the shorter the stopping distance will be.

Question 30

Explain dangers of large decelerations and estimate forces

Question 31

What is momentum? | Equation

Answer 31

A property all moving objects have So a stationary object has no momentum | mass(kg) x velocity(m/s)

Question 32

What is the conservation of momentum?

Answer 32

In a closed system, the total momentum before an event is the same as after the event

Question 33

Describe examples of momentum in collisions

Answer 33

When there is a car crash and lock togrther and carry on moving in the same direction