two electric bulb of 40 w and 60 w connected to 120v line the ratio of there resistance wil be
Answers
1:12 is your right answer to your question
Given:
Power of 1st electric bulb = 40W
Power of 2nd electric bulb = 60W
Potential across them = 120V
To find:
Ratio of resistances of two bulbs.
Solution:
Formula of power dissipated is-
here, P = power dissipated
V = potential across the resistance
I = current flowing across the resistance
In this question, to calculate resistance we will use the below formula,
therefore,
Resistance of first electric bulb will be -
here, P₁ = 40W
V = 120V
R₁ = 360Ω
and, Resistance of second electric bulb is-
R₂ = 240 Ω
Therefore, ratio of first resistance to the second resistance will be,
So, the ratio of resistance having power dissipated value 40W to the resistance having power dissipated value 60W is 3:2.