PHYSICS P2

2019: The frequency of the signal generator is increased. This makes the wavelength of the wave change. The wave speed stays the same.

Describe how the apparatus could be adjusted to show one complete wave without reducing the frequency. (2)

• move the bridge

• to the right

2019: Explain the factors that affect the distance needed to stop a vehicle in an emergency (6)

2019: The greater the braking force, the greater the deceleration of a vehicle

Explain the possible dangers caused by a vehicle having a large deceleration when it is braking (2)

• Brakes overheating or locking

• causing a loss of control or a skid or increasing the braking/stopping distance

2019

• the rods become magnets

• with the same polarity

2019

• changed two independent variables at the same time

• so it is not possible to know the effect of one variable or the other

2019: How does the Big Bang theory describe the start of the universe? (1)

hot and dense

2019

6 × 10²⁴

2019: Explain how the data supports the suggestion that the universe began from a very small region (2)

• the furthest galaxies are moving the fastest

• suggesting the universe is expanding (from a very small region)

2019: An adult of mass of 80kg has more inertia than a child of mass 40 kg

What is inertia? (1)

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

2019: Explain why an egg is less likely to break when dropped on soft foam rather than onto a concrete floor (3)

2019

frequency increases and wave speed in air stays the same

2019: Explain how the properties of x rays make them suitable for medical imaging of bones (2)

• pass through/penetrate soft tissue/skin/muscle

• but absorbed by bone

• at night, more radiation is emitted from the Earth than absorbed from space

• clouds reflect radiation (towards the Earth)

• at A, there is no cloud cover so a larger proportion of radiation will be emitted into space