**Q1 ****Answers**

**Questions**

1)

**Figure 1**shows a circuit diagram containing two identical lamps arranged in parallel.

The reading on the ammeter is 186 mA.

1.1) Which statement about the current through the lamps is true? Tick

**one**box. [1 mark]1.2) One of the lamps breaks and is not replaced.

Which statement about the current in the other lamp is true?

Tick

Which statement about the current in the other lamp is true?

Tick

**one**box. [1 mark]**Figure 2**shows a circuit that can be used to alter the brightness of a lamp.

1.3) The resistance of the variable resistor is increased.

What effect will this have on the brightness of the lamp?

Explain your answer. [2 marks]

When the potential difference across the lamp is 3.3 V, the current is 0.15 A.

1.4) Write down the equation that links current, potential difference and resistance. [1 mark]

Equation _____________________________________________

1.5) Calculate the resistance of the lamp. [3 marks]

What effect will this have on the brightness of the lamp?

Explain your answer. [2 marks]

When the potential difference across the lamp is 3.3 V, the current is 0.15 A.

1.4) Write down the equation that links current, potential difference and resistance. [1 mark]

Equation _____________________________________________

1.5) Calculate the resistance of the lamp. [3 marks]

Resistance = _____________ Ω

1.6) Sketch a current–potential difference graph for a filament lamp. [1 mark]

**(Total for Question 1 = 9 marks)**