Suppose you wanted to do an experiment to find out if changing the length of a pendulum changed the amount of time it takes the pendulum to swing back and forth. Which pendulums from the above diagram would you use for the experiment?

Question

anonymous · Answer

attachment

anonymous · Answer

i thought since it was referring to length it would be 1 and 3, but i googled it and everyone  is saying different answers so im kinda confused :/

anonymous · Answer

these are the choices 
 1 and 4
 2 and 4
 1 and 3
 2 and 5
 all

ganpat · Answer

which one do you think ??

ganpat · Answer

assuming W is weight of the pendulum !!

anonymous · Answer

yes sorry, w is weight.

anonymous · Answer

is it 1 and 4? since theyre the same length?

ganpat · Answer

But you are studying time effect when length of pendulum changes.. so whatever you select should be of different length..

anonymous · Answer

different length but same weight?

anonymous · Answer

so 1 and 3?

ganpat · Answer

perfecto.. weight has to be same so as you can focus on time change because of varying length...

ganpat · Answer

If you vary weight as well, then result will not be accurate and experiment shall fail..

SO 1 & 3 is the right answer...

anonymous · Answer

Thank you so much!!

ganpat · Answer

All the best ! :)

anonymous · Answer

Can i ask one more question please?

anonymous · Answer

if youre changing the weight on the end of the string to still measure the time, the length would need to be the same then?

ganpat · Answer

yup.. so that you could focus on time change due to change in weight..

anonymous · Answer

Thank you so much :) that helps a lot.