Some light bulbs are connected in paralles to 120 V source as shown in the figure .Each bulb dissipates as power of 60 W .The circuit has a fuse F that burns out when the current in the cicuit exceeds 9A .Determine the largest number of bulbs, which can be used in this circuit without burning out the fuse

Options

A. 9
B. 18
C. 25
D. 34

Answer

2

Explanation

`60 = (V^(2))/(R )`
`60= (120xx120)/(R )`
`R=240 Omega`
"Suppose total bulb are N"
`R_(eq)=R/N`
`i=(120)/(R )N`
`(120N)/(R )=9`
`(120 N)/(240)=9`
`N=18`
if N `gt` 18 "bulb get fuse"