Angelique investigates the current in a circuit, and how it changes when the length of a resistance wire is changed. Look at the circuit diagram. The symbol for the variable resistor represents the resistance wire. Look at the table of Angelique's results. Length of resistance wire in cm current in A 10 2 . 0 20 2 . 2 30 0 . 8 40 1 . 2 Do these results fit with your predicted observations? Describe how the results do (or do not) fit your prediction.

Resistance is the property of a conductor which opposes the flow of current passing through it. Resistance R of a wire is directly proportional the length l of the wire. Variable resistor is used to change the resistance in the circuit to analyse the current in the circuit how it varies with the resistance. R ∝ l I = V R (where V is the potential difference of the cell) Since, potential difference is constant in the given circuit, current is inversely proportional to the resistance i.e length of the wire. Hence, the given observations are wrong.

Angelique investigates the current in a circuit, and how it changes when the length of a resistance wire is changed. Look at the circuit diagram. The symbol for the variable resistor represents the resistance wire. Look at the table of Angelique's results. Length of resistance wire in cm current in A 10 2 . 0 20 2 . 2 30 0 . 8 40 1 . 2 Which, if any, lengths of resistance wire should Angelique test again? Explain your answer.

Resistance is the property of a conductor which opposes the flow of current passing through it. Resistance R of a wire is directly proportional the length l of the wire. Variable resistor is used to change the resistance in the circuit to analyse the current in the circuit how it varies with the resistance. R ∝ l I = V R (where V is the potential difference of the cell) Since, potential difference is constant in the given circuit, current is inversely proportional to the resistance i.e length of the wire. Hence, the given observations are wrong. Angelique has to take the readings of 20 cm and 30 cm as they are not proportional to the current in the circuit.

Which circuits include lamps connected in parallel

EASY

Lower Secondary Stage 9

IMPORTANT

Cambridge Lower Secondary Science Stage 9: Workbook>Chapter 9 - Electrostatics and Electric Currents>Test-style questions>Q 2

Angelique investigates the current in a circuit, and how it changes when the length of a resistance wire is changed. Look at the circuit diagram. The symbol for the variable resistor represents the resistance wire.

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Predict what you would expect to observe when the length of resistance wire is changed.

EASY

Lower Secondary Stage 9

IMPORTANT

Cambridge Lower Secondary Science Stage 9: Workbook>Chapter 9 - Electrostatics and Electric Currents>Test-style questions>Q 2

Angelique investigates the current in a circuit, and how it changes when the length of a resistance wire is changed. Look at the circuit diagram. The symbol for the variable resistor represents the resistance wire.

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Look at the table of Angelique's results.

Length of resistance wire in cm	current in A
$10$	$2.0$
$20$	$2.2$
$30$	$0.8$
$40$	$1.2$

Do these results fit with your predicted observations? Describe how the results do (or do not) fit your prediction.

MEDIUM

Lower Secondary Stage 9

IMPORTANT

Cambridge Lower Secondary Science Stage 9: Workbook>Chapter 9 - Electrostatics and Electric Currents>Test-style questions>Q 2

Angelique investigates the current in a circuit, and how it changes when the length of a resistance wire is changed. Look at the circuit diagram. The symbol for the variable resistor represents the resistance wire.

Question Image