A pendulum clock loses 12 s a day if the temperature is 400C and gains 4 s a day if the temperature is 200C. The temperature at which the clock will show correct time, and the co-efficient of linear expansion (α) of the metal of the pendulum shaft are respectively :
250C; α = 1.85×10−5/0C
600C; α =1.85×10−4/0C
300C; α=1.85×10−3/0C
550C; α = 1.85×10−2/0C
As we learnt in
Time period of oscillation of simple pendulum -
- wherein
l = length of pendulum
g = acceleration due to gravity.
Times lost / gained per day
Where Co-efficient of linear expansion.
(i)
(ii)
On dividing we get
After put the value of we get
Correct option is 1.
Option 1)
250C; α = 1.85×10−5/0C
This is the correct option.
Option 2)
600C; α =1.85×10−4/0C
This is an incorrect option.
Option 3)
300C; α=1.85×10−3/0C
This is an incorrect option.
Option 4)
550C; α = 1.85×10−2/0C
This is an incorrect option.
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