Questions Correction 2019

Question 1

Explain the possible dangers by a vehicle having a large deceleration when it is braking

Answer 1

Brakes overheating
Causing a loss of control

Question 2

Explain why iron rods placed inside a solenoid move apart when the switch is closed

Answer 2

Rods become induced magnets
With same polarity

Question 3

6 x 10^12 tetra meters is how many metres

Answer 3

6 x 10^24

Question 4

Give two reasons why peer review is an important process

Answer 4

Detects false claims
Detects bias

Question 5

What is Inertia

Answer 5

The tendency of an object to continue in its state of rest or motion

Question 6

Explain why the egg is less likely to break when dropped onto soft foam rather than onto a concrete floor

Answer 6

Soft foam increases time taken to stop
So decreases the rate of change in momentum
Reducing the force on the egg

Question 7

Explain how properties of X rays make them suitable for the medical imaging of bones

Answer 7

Pass through soft tissues
But absorbed by bone

Question 8

Explain the changing motion of the skydiver in terms of the forces acting on the skydiver

Answer 8

Initially air resistance is less than gravity so skydiver accelerates
Acceleration cause the air resistance to increase
Resultant force decreases to zero
So skydiver falls at terminal velocity

Question 9

What is the function of a microphone

Answer 9

To convert sound into variations of current

Question 10

How does a moving coil microphone work

Answer 10

Sound waves cause diaphragm to vibrate
Diaphragm causes coil to vibrate
The coil cuts through the magnetic field lines
A potential difference is induced