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WorksheetsTransformers
Total questions: 12
Worksheet time: 6mins
A transformer consists of
Metal Core
Metal core and coiled wire
Metal core and polymer wire
Polymer core and metal wire
Transformer is device that
converts AC voltage to current
converts electrical energy to kinetic energy
converts AC voltage to a different level at the same amplitude
converts AC voltage to a different level at the same frequency
Select the facts about transformer.
Will not work with DC and AC
Will not work with DC
AC will produce change in magnetic field
AC will induce current
Is the core insulated?
Yes
No
The insulation at the transformer's core is meant for
to avoid sharp edges.
to avoid corrosion.
to avoid electrical contact.
to reduce power loss.
Primary loop is connected to the supply while secondary loop is connected to the load.
True
False
Step-up transformer is a transformer that increases...
voltage.
current.
resistance.
conductance.
A secondary coil of a transformer has 500 windings. It was supplied with 200 V. How many windings needed at primary coil to produce 100 V.
(a)
A secondary coil of a transformer is supplied with voltage source, while the primary coil induces voltage (emf).
True
False
Select the correct characteristics for ideal transformers.
Zero leakage flux.
The wire have no resistance.
No hysteresis or eddy currents.
Has similar windings at both primary and secondary coils.
Efficiency of a transformer is
(output current)/(input current) x100%
(output voltage)/(input voltage) x100%
(output loss)/(input loss) x100%
(output power)/(input power) x100%
A transformer has an output power of 500W. It also has core losses and copper loss of 10W. Determine the efficiency (%) of the transformer.
(a)
