Exam Questions Flashcards Preview

AQA GCSE Physics > Exam Questions > Flashcards

Flashcards in Exam Questions Deck (9)
Loading flashcards...

A student becomes negatively charged because of the friction between his socks and the carpet. Explain why (2)

Transfer of electrons
from the carpet to the student


The negatively charged student touched a metal tap and receives an electric shock. Explain why (3)

There is a potential difference between student and tap
which causes electrons to transfer from the student to the tap
which earths the charge


Some carpets have thin copper wires running through them. The student is less likely to receive an electric shock after walking on this type of carpet. Suggest why (2)

Carpet/copper has a low resistance
Lower/no build up of charge on student


Write down the equation that links power. time and work done (1)

power = work done/time


Calculate the work done by a cyclist when his power output it 200W for 1800 seconds (3)

200 = W/1800
W = 200 x 1800
W = 360,000 J


The maximum speed a cyclist can travel on a level road is 14 m/s. How does cycling up hill affect the maximum speed of the cyclist? (3)

Maximum speed is lower
because maximum power output is constant
but additional work is done (against gravity)


The current through an ohmic conductor is directly proportional to the _____ across the component, provided that the ______ remains constant (2)

Potential difference


Many households are replacing filament lamps with LEDs, which are more energy efficient. What does more energy efficient mean? (1)

A higher proportion/percentage of the total power/energy input is usefully transferred


Why is it safe to use a source of alpha radiation in smoke alarms in a house?

Alpha radiation is not very penetrating/ does not penetrate skin