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WorksheetsTransformer Voltage Calculations
Total questions: 33
Worksheet time: 52mins
Assume primary has 240 turns and secondary has 60 turns. Primary is connected with 120V AC power supply. What is the voltage on the secondary?
30 V
0.333 V
2 V
120V
The function of a transformer is to ...
raise and lower the apparent power levels
transfer DC voltage from the primary winding to the secondary winding
increase or decrease A.C voltage or A.C current levels
transform mechanical energy into electrical energy
A 12Ω resistor is connected across the secondary winding of an ideal transformer whose secondary voltage is 120V. Determine the primary voltage if the supply current is 4A.
9 kA
0.9 kA
0.9 MA
9 MA
10 W
50 W
2 W
500 W
20 W
0 W
2 W
250 W
10 A
1 A
0.1 A
0.02 A
240 Ω
24 Ω
12 Ω
1.2 Ω
60 V
24 V
12 V
2.4 V
A transformer has 480 primary coils and 120 secondary coils. If the current on the primary side is 12 A, then the current on the secondary side is...
3 amps
4 amps
12 amps
48 amps
none of the above
A transformer has 480 primary coils and 120 secondary coils. If the current on the primary side is 12 A and the power in the primary side is 960 Watts, then the voltage on the secondary side is:
80 Volts
960 Volts
20 Volts
320 Volts
A transformer has 100 turns in the primary coil and 25 turns in the secondary coil. When a 120 V is applied to the primary coil, what is the voltage in the secondary coil?
480V
30V
20V
450V
If the primary power of an ideal transformer having a 2:1 voltage ratio is 100 W, the secondary power is:
200 W
75 W
50 W
100 W
If a transformer reduces voltage, it is called a....................... transformer.
step left
step right
step up
step down
Calculate potential difference in the secondary coil based on the information given below.
Vp = 240 V
Np = 20
Ns = 125
Vs ?
1500
500
1000
2000
Calculate voltage in the secondary coil based on the information given below.
Vp = 240 V
Np = 20
Ns = 125
Vs ?
1500 Turns
1500 V
1500A
In a 12 V transformer connected to a regular 120 V /5 A line. the output current will be
50 A
20 A
1.2 A
In a 12 V transformer connected to a regular 120 V /5 A line. the output current will be
50 A
20 A
1.2 A
In a transformer with 200 turns in the primary coil and 25 turns in the secondary coil the ratio will be...
1:8
8:1
12:1
A transformer has a source voltage of 50 volts ac, with a turns ratio of 1:6. What is the voltage of the secondary winding?
150
300
500
600
A transformer has a 5:1 turns ratio; 20 volts are induced in the secondary. What is the primary voltage?
100 volts
50 volts
10 volts
4 volts
A transformer has thirty-five volts applied to its primary induces 105 volts in its secondary. The secondary is composed of 99 turns. What is the number of turns in the primary?
11 turns
22 turns
33 turns
44 turns
A step-up transformer has 200 turns in the primary coil and 800 turns in the secondary coil.
If the primary voltage is 120V, what is the secondary voltage?
Use this to determine the current through a 50Ω resistor connected to the secondary.
Calculate Power
A step-down transformer reduces voltage from 480V to 120V. If the primary coil has 1000 turns, how many turns are in the secondary coil?
A step-down transformer reduces voltage from 480V to 120V. The primary coil has 1000 turns. Calculate the current in a 20Ω resistor connected to the secondary.
A(n) _______is a device used to increase or decrease the voltage of an electricity supply. They are designed to be as efficient as possible (up to 99.9% efficient).
transformer
transmitter
windmill
firestation
A step-down transformer reduces voltage from 480V to 120V. The primary coil has 1000 turns. Calculate the power dissipated in a 20Ω resistor connected to the secondary.
A transformer has a turn ratio of 5:1. If the primary current is 4A, what is the secondary current?
A transformer has a turn ratio of 5:1 and the primary current is 4A. Determine the secondary voltage if the primary voltage is 250V.
A transformer has a turn ratio of 5:1 and the primary current is 4A. Find the power consumed by a 10Ω resistor in the secondary circuit.
