4 marksFoundation and Higher
Radium-226 decays by emitting an alpha particle:
88226Ra→ZARn+24He.1Determine the mass number A of the radon nucleus.
[1 mark] .2Determine the atomic number Z of the radon nucleus.
[1 mark] .3Strontium-90 decays by beta emission. Describe what happens in the nucleus during beta decay.
[2 marks] 6 marksFoundation and Higher
A tired driver is driving fast on a wet road at night.
Explain how each of these factors affects the stopping distance of the car.
[6 marks]7 marksFoundation and Higher
Waves travel across a pond. A floating leaf moves up and down 5 times in 2.0 s. The distance between neighbouring crests is 0.40 m.
.1Calculate the frequency of the waves.
[1 mark] .2Calculate the speed of the waves.
[2 marks] .3Calculate the period of the waves.
[2 marks] .4The leaf moves up and down but does not travel across the pond with the waves.
Explain what this shows about the waves.
[2 marks] 6 marksFoundation and Higher
An electric motor in a lift raises the lift through a height of 12 m in 20 s. The mass of the lift is 800 kg.
Gravitational field strength = 9.8 N/kg.
.1Calculate the energy transferred to the lift's gravitational potential store.
[2 marks] .2Calculate the useful power output of the motor.
[2 marks] .3A second motor raises the same lift through the same height in 30 s.
Explain why the second motor has a lower power output.
[2 marks] 4 marksFoundation
An electric kettle has an input power of 2000 W. The useful power output, heating the water, is 1800 W.
.1Calculate the efficiency of the kettle.
[2 marks] .2Calculate the power wasted by the kettle.
[1 mark] .3Give one way energy is wasted by the kettle.
[1 mark] 