P5-forces

Question 1

what is scaler

Answer 1

only has magnitude( size)

Question 2

examples of scaler

Answer 2

mass
temperature
speed
time
distance
energy

Question 3

what is vector

Answer 3

both magnitude and direct

Question 4

examples of vector

Answer 4

force
velocity
acceleration
displacement
weight

Question 5

what is a force

Answer 5

A force is a push or a pull that acts on an object due to interaction with another object and are measured in Newtons.

Question 6

what are two types of forces with examples?

Answer 6

contact forces
non contact force

Question 7

what is a contact force?
examples of contact force

Answer 7

2 objects that are physically touching for the force to occur. eg. friction/air resistance

Question 8

what is a non contact force?
examples of a non contact force

Answer 8

2 objects that dont need to physically be touching for the force to occur
eg. magnetic force, gravitation potential force

Question 9

what is mass?

Answer 9

how much matter the object has in it (Scaler)
mass does not depend on where the object is

Question 10

what is weight?

Answer 10

the force acting on an object due to gravity.
weight does depend on where the object is

Question 11

describe the relationship between the mass and weight of an object

Answer 11

the mass of an object is directly proportional to the weight of an object

Question 12

how do we measure weight?

Answer 12

using a newton meter

Question 13

what is the centre of mass

Answer 13

The weight of an object (the force due to gravity) can
be considered to act a single point.

Question 14

what is a resultant force

Answer 14

a single force that has the same
effect as all of the original forces acting together.
To work it out you do larger force minus smaller force

Question 15

what is work done

Answer 15

the amount of force needed to move an object a certain distance

Question 16

what is elastic deformation

Answer 16

Once the forces are removed, then it returns to its original
shape and length.

Question 17

what is inelastic deformation

Answer 17

Once the forces are removed, then the material does not
return to its original shape and length.

Question 18

what is distance

Answer 18

How far an object moves.
as it doesnt involve direction it is scaler.

Question 19

what is displacement

Answer 19

the distance an object moves in a straight line from the start
point to the finish point and the direction of that straight line.

Question 20

what is speed

Answer 20

how fast you are going with no regard to the direction.

Question 21

what is velocity

Answer 21

the direction and the speed

Question 22

what are the typical speeds

Answer 22

normal walking speed-1.5m/s
running speed- 3m/s
cycling speed 6m/s

Question 23

what factors can speed depend on

Answer 23

fitness- the younger the fitter a person the quicker they will be
terrain- smoother ground is better compared to hills
distance travelled- if you run a long distance you start off faster

Question 23

more speeds you may be asked about

Answer 23

car on main road- 13m/s
fast train in uk- 50m/s
cruising aeroplane 250m/s
speed of sound in air 330m/s

Question 24

important things to know for acceleration 1/2 graphs

Answer 24

The gradient = acceleration
Flat section represent steady speed
The steeper the graph, the greater the
acceleration/deceleration
Uphill sections (/) are acceleration
Downhill sections () are deceleration
A curve represent changing acceleration
The area under the graph represents the distance
travelled

Question 25

important things to know for distant time graphs

Answer 25

The gradient = speed
flat section are where it’s stopped
The steeper the slope, the faster it is going
Downhill sections means that it’s going towards its
starting point.
Curves represent acceleration
A steepening curve means it’s speeding up
A leaving off curve means it’s slowing down

Question 26

how to calculate speed

Answer 26

first draw a tangent
then calculate a gradient (change in y divide change in x)

Question 27

what is acceleration

Answer 27

Acceleration is how quickly something is speeding up

Question 28

what is terminal velocity

Answer 28

air resistance is equal to gravity
when the object stops accelerating and moves at a constant speed.

Question 29

what is newtons 1st law

Answer 29

The velocity of an object will only change if a resultant force is acting on the object.

Question 30

what is newtons 2nd law

Answer 30

The acceleration of an object is proportional to the resultant
force acting on the object and inversely proportional to the mass of the object.

Question 31

what is newtons third law

Answer 31

when two objects interact, they exert equal and opposite forces on each other

Question 32

what is stopping distance

Answer 32

distance during the drivers thinking time (notices the object) till he actually applies the break and stops

Question 33

what is thinking time

Answer 33

– the time taken between
seeing the hazard and hitting the brakes. Typical range 0.4s to
0.9s

Question 34

what is braking distance

Answer 34

the time taken between applying the brakes and the car stopping.

Question 35

factors affecting thinking distance

Answer 35

-tiredness
-poor visibility
-too much alcohol
too many drugs

Question 36

factors affecting braking distance

Answer 36

wet roads
icy roads
driving too fast
tyres/brakes worn out

Question 37

what is momentum

Answer 37

an object’s mass and velocity

Question 38

what is the conservation of momentum

Answer 38

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