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A step-down transformer is connected to ...

A step-down transformer is connected to main supply `200V` to operate a `6V`, `30W` bulb. The current in primary is

A

`3A`

B

1.5 A

C

0.3 A

D

0.15 A

Text Solution

Verified by Experts

The correct Answer is:
D
`P_(P)=P_(S)`
`I_(P)*e_(P)=P_(S)`
`I_(P)=(P_(S))/(e_(P))=(30)/(200)=0.15A`
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