P:2 Electricity Paper 1

Question 1

Write a Definition of Current and What’s It Mesured in?

Answer 1

• Current is the Flow of Electrons around a circuit.
• Current is Mesured in Amperes (A).

Question 2

Write a Definition of Potential Difference and What’s it Mesured in?

Answer 2

• Potential Difference is the force driving the flow of electrons.
• Potential Difference/ Voltage is Mesured in Volts (V).

Question 3

Write a Definition of Resistance and What’s It Mesured in?

Answer 3

• Resistance is Everything that resists or opposes the flow of electrons.
• Resistance is Mesured in Ohms (Ω)

Question 4

Which Way does Current Flow In a Circuit?

Answer 4

• Current Always Flows from the Positive (Right) to negative (Left)

Question 5

What Does the Current through a Component depend on?

Answer 5

• The current through a Component depend on both the Resistance (R) of the component and the Potential Difference across the component.

Question 6

What happens if the Resistance is Greater?

Answer 6

• The greater the Resistance of the component the smaller the current for giving potential difference across the component.

Question 7

What is The equation for Potential Difference?

Answer 7

• Potential difference (V) = Current (A) X Resistance (R).

Question 8

What happens in some Resistors in Terms of value?

Answer 8

• the Values of Resistors should remain constant but t can change as current changers.

Question 9

What Happens If the Current in an Ohmic Conductor Remains constant?

Answer 9

• The current in a Ohmic conductor (At a constant temperature) is directly proportional to the potential difference across the resistor.

Question 10

What happens in the resistance in some components?

Answer 10

• The resistance in some components such as lamps, diodes, thermistors and LDRs is not constant it changes with the current through the component.

Question 11

What happens in the resistance of a filament lamp?

Answer 11

• The Resistance of a filament lamp increases as the temperature of the filament lamp.

Question 12

What happens in a Current through a Diode?

Answer 12

• The current through a diode flows in 1 direction only. the Diode has a very high resistance in the reverse direction.

Question 13

What happens to the Resistance of a Thermistor if the temperature increases?

Answer 13

• The resistance of a thermistor decreases as the temp increases.

Question 14

What Happens to the Light Intensity of the LDR Decreases?

Answer 14

• The resistance of an LDR Decreases as the light intensity increases.