Transformer

The thin sheets of steel from which transformer cores are made are called...................

• lamination

• transformer

• copper

The value of the second winding voltage of an iron-core transformer depends upon the ....... of turns, this winding contains as compared to the number of ........ winding turns.

• primary, size

• number, primary

• size, height

• number, size

Why transformers work with A.C. current but not D.C.

• A.C current produces changing magnetic field.

• D.C current produces changing magnetic field.

• D.C current is weak

• A.C current is powerful

Tags

NGSS.HS-PS2-5

NGSS.HS-PS3-5

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

This picture is an example of a ___________

• Step- Up Transformer

• Step- Down Transformer

• Motor

• Generator

Tags

NGSS.HS-PS2-5

NGSS.HS-PS3-3

This picture is an example of a ___________

• Step- Up Transformer

• Step- Down Transformer

• DC Motor

• AC Generator

Tags

NGSS.HS-PS3-3

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

Ratio of voltages is equal to ratio of

• iron sheets in core

• coil

• number of turns in coil

• all of above

Will a transformer work with direct current (d.c.) or alternating current (a.c.)?

• a.c. only

• d.c. only

• Both a.c. and d.c.

Tags

NGSS.HS-PS2-5

Transformer is always connected to ___________ supply.

• A.C.

• D.C.