Electricity - AQA GCSE

Front

What does it mean that LED lamps are more efficient than filament lamps?

Back

LED lamps waste a smaller proportion of the input energy than filament lamps.

Front

What is the formula to calculate potential difference (V) across a resistor?

Back

V = I × R, where I is the current in Amperes and R is the resistance in Ohms.

Front

Calculate the potential difference across a 45 Ω resistor with a current of 0.10 A. (2 sig fig, no units needed)

Back

4.5

Front

What is the unit of electric charge?

Back

Coulomb (C)

Front

How do you calculate the charge (Q) that flows through a circuit?

Back

Q = I × t, where I is the current in Amperes and t is the time in seconds.

Front

Calculate the charge that flows through a thermistor in 5 minutes with a current of 3.5 mA. (answer to 3 sig fig, no units needed)

Back

1.05

Front

What happens to the charge of an object when it is rubbed with a cloth?

Back

The object can become charged due to the transfer of electrons.

Front

If a plastic strip becomes negatively charged after rubbing, what charge does the cloth acquire?

Back

Positive charge.

Front

What is the relationship between current (I), voltage (V), and resistance (R) in a circuit?

Back

Ohm's Law: V = I × R.

Front

What is the normal current through a filament lamp mentioned in the graph?

Back

1.5 A.