Question

Two resistances of 20watt and 40watt are connected in series to a battery of potential difference 10volt. Compare the ratio of the heat produced in one minute in the two resistances

Answer 1

Answer:

5/8

Explanation:

V = IR , I = V/R

LET R 1 = 20 ohm , R 2 = 40 ohm

for R 1 , I = 10/20 , = 0.5 A

for R 1 , I = 40/20 , = 2 A

heat in R 1 , H 1= l^2R 1 t

= (0.5)^2×20×60 , = 5×60

heat in R 2 , H 2= I^2R 2 t

= (2)^2×2×60 , = 8×60

ratio of heat is = H 1/H 2

= 5×60/8×60 , =5/8