Pendulum clock when taken to moon

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utkarshakash
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Homework Statement


A pendulum clock that keeps correct time on the Earth is taken to the moon. It will run

a) at correct rate
b)6 times faster
c)√6 times faster
d)√6 times slower

Homework Equations



The Attempt at a Solution


[itex]T_{earth} = 2\pi \sqrt{\dfrac{L}{g}} \\<br /> T_{moon} = 2\pi \sqrt{\dfrac{L}{g/6}}[/itex]

Dividing i) by ii)

[itex]\dfrac{T_{earth}}{T_{moon}} = \frac{1}{√6} \\<br /> T_{moon} = √6T_{earth}[/itex]

This implies option c) is correct but my book says it is option d).
 
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utkarshakash said:

Homework Statement


A pendulum clock that keeps correct time on the Earth is taken to the moon. It will run

a) at correct rate
b)6 times faster
c)√6 times faster
d)√6 times slower

Homework Equations



The Attempt at a Solution


[itex]T_{earth} = 2\pi \sqrt{\dfrac{L}{g}} \\<br /> T_{moon} = 2\pi \sqrt{\dfrac{L}{g/6}}[/itex]

Dividing i) by ii)

[itex]\dfrac{T_{earth}}{T_{moon}} = \frac{1}{√6} \\<br /> T_{moon} = √6T_{earth}[/itex]

This implies option c) is correct but my book says it is option d).

Use concept ,

T [itex]\alpha[/itex] 1/√g

As √g reduces by √6 on moon , this implies time period on moon will be √6 times that of Earth , as you got. You interpreted your answer wrongly. If the time period increases , pendulum will oscillate slower or faster for a given displacement of the bob ?
 
sankalpmittal said:
Use concept ,

T [itex]\alpha[/itex] 1/√g

As √g reduces by √6 on moon , this implies time period on moon will be √6 times that of Earth , as you got. You interpreted your answer wrongly. If the time period increases , pendulum will oscillate slower or faster for a given displacement of the bob ?

Thanks for pointing out my mistake
 
utkarshakash said:


This implies option c) is correct but my book says it is option d).


Forget the math for a minute and just think about it logically. Would you really expect a pendulum clock when moved to lower gravity to have the pendulum swing FASTER? Really ?