Section 1: Forces And Motion

Question 1

Know and use the relationship between acceleration, velocity and time

Answer 1

Acceleration = Change In Speed/Time

Question 2

Determine acceleration from the gradient of a velocity-time graph

Answer 2

Acceleration = Rise/Run

Question 3

Determine the distance travelled from the area between a velocity-time graph and the time axis.

Answer 3

The area under a Velocity time graph is equal to the distance travelled.

Question 4

Identify different types of force

Answer 4

Kinetic, Potential, Electrical, Nuclear, Light, Sound and Heat

Question 5

Distinguish between vector and scalar quantities

Answer 5

Vector: Has a Quantity and a Direction
Scalar: Has a Quantity but No Direction

Question 6

Know and use the relationship between unbalanced force, mass and acceleration

Answer 6

Force = Mass × Acceleration

Question 7

Know and use the relationship between Weight, Mass and Gravity:

Answer 7

Weight = Mass × Gravity

Question 8

Describe the forces acting on falling objects and explain why falling objects reach a terminal velocity

Answer 8

When dropped the object experiences massive acceleration due to gravity. This acceleration slows due to the air resistance balancing acting on the object with the gravity. Eventually the gravity is equal to the air resistance and the speed is constant.

Question 9

Describe experiments to investigate the forces acting on falling objects, such as sycamore seeds or parachutes

Answer 9

Dropping parachutes from a given height; this shows us that gravity is acting on them. By increasing the size of the parachute and recording the results we can see that air resistance also has an effect on falling objects; plotting a graph should reveal that bigger surface area takes more time, from which we can infer that air resistance acts on the falling objects.

Question 10

Describe the factors affecting vehicle stopping distance including speed, mass, road condition and reaction time

Answer 10

The higher the speed the longer the stopping distance
The heavier the vehicle the longer the stopping distance
If the road is damp the stopping distance increases
The longer the reaction time (due to alcohol tiredness ECT), the longer the stopping distance

Question 11

Know and use the relationship between momentum, mass and velocity:

Answer 11

Momentum = Mass × Velocity

Question 12

Use the idea of momentum to explain safety features

Answer 12

Airbags: Rapidly expand in order to slow people down and don’t allow them to hit the surfaces of the car
Seatbelts: Hold people in place so they don’t fly forewords during a crash
Crumple Zones: Slow the car down rather then stopping it all at once

Question 13

Use the relationship between force, change in momentum and time taken

Answer 13

Force = Change in Momentum

Question 14

Demonstrate an understanding of Newton’s third law

Answer 14

Newton’s Third Law is: “For every action, there is an equal and opposite reaction.”

Question 15

Know and use the relationship between the moment of a force and its distance from the pivot:

Answer 15

Moment = Force × Distance

Question 16

Recall that the weight of a body acts through its center of gravity

Answer 16

The weight of a body acts through its center of gravity, at this point the weight is equally dispersed in all directions

Question 17

Describe experiments to investigate how extension varies with applied force for helical springs, metal wires and rubber bands

Answer 17

Clamp a spring to a clamp stand. Put weight on spring. Measure extension of the spring. Repeat with different weight. Use F=KE to work out spring constant

Question 18

Describe elastic behavior as the ability of a material to recover its original shape after the forces causing deformation have been removed.

Answer 18

Materials can return to there original shape once tension is released until they reach there limit of elasticity

Question 19

Describe experiments to investigate the motion of everyday objects

Answer 19

Find a 1 meter ramp
Find a wheeled trolley
Let the trolley roll down the ramp and time the time taken for it to reach the bottom. Repeat this with a different angle each time