# P2.3 Currents in electrical circuits Flashcards Preview

## GSHS P2.3 Currents in electrical circuits > P2.3 Currents in electrical circuits > Flashcards

Flashcards in P2.3 Currents in electrical circuits Deck (18)
1
Q
1. Describe how an insulator becomes charged?
A
1. Rubbing / friction transfers electrons
2
Q
1. What would happen if two positively charged objects were brought next to each other?
A
1. repel
3
Q
1. Describe (in terms of electrons and charges) what happens when a charged balloon is brought close to a wall.
A
1. Balloon is negatively charged, it repels the electrons in the wall, it is attracted to the positive charge left in the wall.
4
Q
1. Define an ‘electric current’ and state what this is in metals.
A
1. The flow of charge, the flow of electrons
5
Q
1. What type of current do cells and batteries provide?
A
1. direct current
6
Q
1. How should you put an ammeter into a circuit and what does it measure? Give the units
A
1. In series, current, Amps
7
Q
1. What is another name for voltage?
A
1. Potential Difference
8
Q
1. What will happen to the current if the potential difference is increased?
A
1. Increase
9
Q
1. How should you put a voltmeter into a circuit and what does it measure? Give the units
A
1. In parallel, voltage or p.d., volts
10
Q
1. Define potential difference
A
1. 1 Volt is the energy transferred per unit charge/1 joule per coulomb
11
Q
1. Name 3 components shown as an I-V plot?
A

Filament lamp, Resistor and Diode.

12
Q
1. Explain the effect of increasing resistance on current.
A
1. Reduces current because it is more difficult for the electrons to flow.
13
Q
1. What p.d. is needed to make a 2A current flow through a 10ohm resistor?
A
1. 2x10=20V
14
Q
1. What happens to the resistance of a filament amp after it is turned on? How does this affect current?
A
1. Resistance increases, current decreases.
15
Q
1. What happens to the resistance of a LDR as light intensity increases? What effect does this have on current?
A
1. Resistance decreases, current increases.
16
Q
1. Explain what happens to a resistor as current passes through it?
A
1. Heats up because there are collisions between electrons and the ions in the lattice.
17
Q
1. Give a use of the heating effect of a wire
A
1. Heating element in kettle, fire etc.
18
Q
1. Why is there an increasing use of LEDs for lighting?
A
1. They use a much smaller current than other forms of lighting.