Questions Corrections 2021

Question 1

Explain the effect of a factor on the braking distance

Answer 1

Increased mass of car
Increased kinetic energy of car so more work needs to be done to stop the car

Question 2

Explain why the star is stable while it is in the main sequence stage of its life cycle

Answer 2

Gravitational force inwards
And forces as a result of fusion reactions outwards
Are balanced

Question 3

Describe what will happen to the star (same mass of the sun) between the main sequence stage and the end of the stars life cycle

Answer 3

Star will expand to become a red giant
And collapse to become a white dwarf
And then cool to become a black dwarf

Question 4

Explain why the blue object appeared black under the red light filter

Answer 4

Only red is transmitted by the filter
Red is absorbed by the object
So no light is reflected by the blue object

Question 5

One use of UV

Answer 5

Sterilise equipment

Question 6

Explain how a moving coil loudspeaker produces a sound wave

Answer 6

Current creates a magnetic field
Which interacts with the permanent magnet field
Producing a force causing the coil to move
When the current reverses the direction of the force reverses producing a sound wave

Question 7

Explain how Flemings left hand rule can be used to predict the direction in which the copper rod will move

Answer 7

Hold thumb first finger and second finger at right angles to each other
Second finger represents the current (say direction it points)
First finger represents field (state which direction it points)
And thumb points in the direction of the force
(Say where the rod moves)