Incandescent bulbs are designed by keeping in mind that the resistance of their filament increases with the increase in temperature. If at room temperature, `100W, 60W and 40W` bulbs have filament resistances `R_(100), R_(60) and R_(40)`, respectively, the relation between these resistances isA. `(1)/(R_(100))=(1)/(R_(40))+(1)/(E_(60))`B. `R_(100)=R_(40)+R_(60)`C. `R_(100)gtR_(60)gtR_(40)`D. `(1)/(R_(100))gt(1)/(R_(60))gt(1)/(R_(40))`

Incandescent bulbs are designed by keeping in mind that the resistance

1.	Incandescent bulbs are designed by keeping in mind that the resistance of their filament increases with the increase in temperature. If at room temperature, `100W, 60W and 40W` bulbs have filament resistances `R_(100), R_(60) and R_(40)`, respectively, the relation between these resistances isA. `(1)/(R_(100))=(1)/(R_(40))+(1)/(E_(60))`B. `R_(100)=R_(40)+R_(60)`C. `R_(100)gtR_(60)gtR_(40)`D. `(1)/(R_(100))gt(1)/(R_(60))gt(1)/(R_(40))`
Answer» Correct Answer - D `R_(100) = (V^2)/(100), R_(60) = (V^2)/(60), R_(40) = (V^2)/(40)` `(1)/(R_(100)) gt (1)/(R_60) gt 1/(R_40)`.

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