2019 paper 1

Question 1

In addition to power input, light bulbs should also be labelled with the rate at which they emit visible light

Answer 1

-bulbs also transfer thermal energy
-so efficiency must also be considered

Question 2

Suggest how electric car batteries could be used to meet sudden peaks in electricity demand

Answer 2

-when cars are plugged in
the energy from car batteries could be transferred back to the National Grid

Question 3

Explain why contamination of the inside of the human body by a radioactive material that emits alpha radiation is highly dangerous

Answer 3

-alpha radiation is highly ionising
-higher risk of cancer
-until the radioactive material is removed

Question 4

Explain why different people have different speeds at the end of the zip wire

Answer 4

-people have different masses
-so people have different terminal velocities

Question 5

Explain how the internal energy of some water changes (in beaker) when it is being heated for 20 degrees to 25 degrees

Answer 5

-the kinetic energy of the particles increases
-which increases the energy of the water

Question 6

How is the particle model used to explain the difference in density between a liquid and a gas

Answer 6

-particles in a gas have more potential energy than particles in a liquid