Forces And Motion

Question 1

What is a moment?

Answer 1

The turning effect of a force

Question 2

Moment equation

Answer 2

Moment=force x distance

Force in Newtons(N)
Distance in meters(M)
Moment in newton meters(Nm)

Question 3

What is Newtons sexond law of motion?

Answer 3

If the forces acting on an object are balanced the resultant force on the object is zero: and if the object is at rest it stays stationary
If the object is moving it keeps moving with the same speed and in the same direction

Question 4

How can we tell if an object is stationary?

Answer 4

The forces will be equal and 0
If it was moving they would be equal and a certain force e.g 20N

Question 5

What is equilibrium

Answer 5

a state when au tone, acting on an
ant are balanced

Question 6

How are levers and gears simple machines

Answer 6

• Both levers and gears use mechanical force
  they have several parts such as pivot loads
  Which then function to be force multipliers or distance
  multipliers and work together to perform a tasks

Question 7

Principles of moments

Answer 7

At equilibrium the sum of anti-clockwise moments f1 x d is equal to the sum of clockwise moments f2 x d

Question 8

What is centre of mass

Answer 8

the centre of mass is the point in an
object where the mass seems to be concentrated

Question 9

What does each characteristic of a distance time graph mean

Answer 9

Gradient= speed (steeper = greater speed)
Flat sections=stationary
straight uphill sections=traveling at a steady
speed.
A steepening curve speeding up
leveling curve means slowing down

Question 10

Method for parallelogram of forces diagram

Answer 10

1. choose a scale
2. Draw the forces to scale in the correct
   direction north, east, south, west)
3. Draw a move was to make a parer engram
   a. Draw a diagonal to the opposite come
   to snow the resultant tone
   s. use a protractor to measure the angle ana desena
   the direction e, east or north

Question 11

Characteristics of a velocity time graph

Answer 11

Are underneath lines is the distance
Gradient-acceleration
* at sections-constant
velocity
steeper graph greater
acceleration/deceleration
uphill sections-acceleration
Downnin sections. dearest.
curve-changing deceleration

Question 12

Newton’s second law

Answer 12

If the forces of an object an
unbalanced, two things about the
object can change.
the speed of the object, it may
Increase or decrease

And the direction?

Question 13

What is a vector quantity?

Answer 13

Vector quantity’s have a magnitude and a direction

Question 14

What are scalar quantities

Answer 14

Scalar quantities have a magnitude minute no direction.

Question 15

Examples of vector quantities

Answer 15

Force, velocity,acceleration, displacement,momentum

Question 16

Examples of scalar quantities

Answer 16

Mass, speed, distance,time

Question 17

What is intertia?

Answer 17

The tendency for an object to stay at rest or continue in uniform(the tendency for motion to remain unchanged)

Question 18

What is stopping distance ?

Answer 18

The stopping distance is the total distance from when
the driver first spots the obstruction to an when the car stops coming to a stationary halt

Stopping distance= thinking distance+ braking distance

Question 19

What is thinking distance?

Answer 19

The distance travelled by the car during the drivers reaction time

Question 20

Factors that affect stopping distances

Answer 20

• Tiredness, alcohol and drugs can an increase thinking distance
• speed of vehicle = further it travels before
it stops
• Adverse road conditions e.g. Icy, wet =stopping a distance or increases due to braking distance increases
• poorly maintained vehicles. e.g worn tyres or brakes

Question 21

What is terminal velocity

Answer 21

Terminal velocity is the top speed of a body
as it falls through a fluid when the weight force
is equal to drag force.

Question 22

What is an elastic collision

Answer 22

Elastic collisions-A perfectly elastic collision
is defined as a collision which there is no loss
of Ek in the collision

Question 23

What is an in elastic collision

Answer 23

Inelastic collisions-part of Ek is changed
to some other form of energy in the collision.

Question 24

What is momentum

Answer 24

momentum is a measure at how difficult it
is to stop a moving object

Question 25

Why are cars designed to have safety features

Answer 25

cars are designed to have features to slow
people down over a longer time this increase this takes longer for a change in momentum. Therefore
the smaller the rate of change in momentum the
smaller the impact tone. smaller force means less serin
injuries

Question 26

Safety features of cars

Answer 26

Crumples zone rumples on impact increasing time creating a longer time for change in Momentum

Seat belts stretch increases time for wearer to stop
Air bags filled with compressed air stop you from hitting dashboard and slow you down more gradually

Question 27

What is hookes
law

Answer 27

The more force put on a material the more it
extends.

Question 28

Write/ explain the method for the hookes law practical

Answer 28

1. set up a retort stand. attach a clamp to
   retort stand using a boss.
2. attach the spring to the clamp (closing jaw
   of clamp)
3. position retort stand over table
4. measure starting length of spring using a
   meter rule and record in a table
   5.add a 1N mass onto the spring
   6.work out extension ( minus new length from
   original)
5. repeat 8 more times increasing the weight
   by 1N each time
6. repeat whole investigation 3 more times and calculate
   a mean
   9.record results in a table
   10.Plot results on a graph
   11.write a conclusion

Question 29

How is pressure transmitted through a liquid?

Answer 29

Equally in a all directions

Question 30

What is resultant force?

Answer 30

The sum of all the forces acting on an object

Question 31

What is Newton’s first law

Answer 31

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

Question 32

What is resultant force

Answer 32

The resultant force is the overall force acting on an object , taking into Account all the different forces acting on it

Question 33

Which two properties if an object may be affected by a resultant force

Answer 33

Speed and direction