Electric Circuits Answers

A galvanometer with coil resistance
12.0Ω
12.0Ω
shows full scale deflection for a current of 2.5mA. How would you convert it into a voltmeter of range 0 to 10.0V?

3988Ω
3988Ω
in series

0.43Ω
0.43Ω
in parallel

Ω
Ω
in parallel

1.62Ω
1.62Ω
in series

A galvanometer of resistance
120Ω
120Ω
a full scale deflection with a current of 0.0005A. How would you convert it to an ammeter that reads a maximum current of 5A?
connect
2000Ω
2000Ω
in parallel to it
connect
200.12Ω
200.12Ω
in series to it
connect $20.10\Omega$$ in series to it
connect
0.012Ω
0.012Ω
in parallel to it

A
2Ω
2Ω
and a
3Ω
3Ω
resistors in parallel are connected in series to a
4Ω
4Ω
resistor.The combination is then connected across a 12V battery having internal resistance of
1Ω
1Ω. What is the equivalent resistance of the circuit?

Electrical energy is sold by PHCN in units of kilowatt-hour (kWh). The lighting of a house is done with five 60W bulbs which are swithed on for approximately three hours per day. What is the lighting bill for the household over a period of 30days at the rate of N1.20 per kilowatt-hour?
N1.50
N25.30
N32.40
N52.20

A battery has emf 13.2V and internal resistance
24mΩ
24mΩ
. If the load current is 20.0A, find the terminal voltage o f the battery
12.7V
14.5V
16.8V
17.7V

A battery charger supplies 10 A to charge a storage battery which has an open - circuit voltage of 5.6 V. If the voltmeter connected across the charger reads 6.8V, what is the internal resistance of the battery at this time?

1.3Ω
1.3Ω

0.52Ω
0.52Ω

0.12Ω
0.12Ω

2.1Ω
2.1Ω

A nicrome wire is 1.0m long and
1.0mm2
1.0mm2
in cross-sectional area. It carries a current of 4.0 A when a potential difference of 2 V is applied between its ends. Calculate the conductivity of the wire.

(2MΩm)−1
(2MΩm)−1

(4kΩm)−1
(4kΩm)−1

(2mΩm)−1
(2mΩm)−1

(4Ωm)−1

The current I in a conductor as a function of time t is given as
I(t)=5t2−3t+10
I(t)=5t2−3t+10
where current is in ampres A and t is in seconds s. What quantity of charge moves across a section through the conductor during the interval t=2s to t=5s?
154.4C
193.5C
225.5C
300.0C

A copper wire has resistance of
2.0Ω
2.0Ω
at
0oC
0oC
and
2.26Ω
2.26Ω
at
30oC
30oC
. What is its resistance at
50oC
50oC
?

2.43Ω
2.43Ω

3.34Ω
3.34Ω

1.52Ω
1.52Ω

5.31Ω
5.31Ω