Current Electricity and Electrical InstrumentHard
Question
If the length of the filament f a heater is reduced by 10 %, the power of the heater will
Options
A.increase by about 9%
B.increase by about 11 %
C.increase by about 19 %
D.decrease by about 10%
Solution
P ⇒ 
......(i)
......(ii)
from eq. (i) & (ii) P′ =
P
× 100 ⇒ 
× 100 ⇒ 
× 100 ⇒ 11.11 %
......(i) ......(ii)from eq. (i) & (ii) P′ =
P × 100 ⇒ × 100 ⇒ × 100 ⇒ 11.11 %Create a free account to view solution
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