a factory is served by a `220 V` supply line . In a circuit protected by a fise marjed `10 A` , the maximum number of `100 W` lamps in parallel that can be turned on is

Options

A. `2`
B. `19`
C. `20`
D. `4`

Answer

B

Explanation

Watt ` = "volt xx ampere"`
`rArr 60 = 230 xx I or = (6//23) A`
If `n` lamps are used in parallel , each allowing `6// 23 A` , then total current , `n xx ( 6 // 23 ) lt = 5`
or `n le 19.1 or n = 19 `