Pendulum Pair
https://isaacphysics.org/questions/pendulum_pair?board=d43a5a20-2f1c-4df2-a833-a457bf2cb206&stage=a_level
I've tried to just difference the times but I feel like im missing another equation to use or im doing smth wrong. Any help would be greatly appreciated.
I've tried to just difference the times but I feel like im missing another equation to use or im doing smth wrong. Any help would be greatly appreciated.
Working: 
Original post by mosaurlodon
Working:
2pisqrt(l/g)
and you want to think about how the period(s) relate to breaking the laser beam for the two pendulums. The actual perturbation is a bit of a red herring.
Also the hints suggest thinking about the shorter pendulum first, then the longer one and thats a good hint.
(edited 1 month ago)
ok I've considered the shorter pendulum first:
Though now im not sure what the time difference represents - is this value equal to 0.3s - how is the difference between the times determined?
Though now im not sure what the time difference represents - is this value equal to 0.3s - how is the difference between the times determined?
Original post by mosaurlodon
ok I've considered the shorter pendulum first:
Though now im not sure what the time difference represents - is this value equal to 0.3s - how is the difference between the times determined?
Though now im not sure what the time difference represents - is this value equal to 0.3s - how is the difference between the times determined?
Id use a more descriptive label(s) for time, so 1/4 period until it first cuts, then 3/4 period until it cuts again or by symmetry, 0.3 s must be a 1/2 period.
Then think about the second pendulum and how to minimise the (total) length.
(edited 1 month ago)
Ok I think I get what the question is asking?
So the time taken for the first pendulum to complete a half period is 0.3s so I can work out l1.
In this time the second pendulum completes a quarter period barely reaching the laser (which I think would give the lowest length) so I can work out l2.
So the time taken for the first pendulum to complete a half period is 0.3s so I can work out l1.
In this time the second pendulum completes a quarter period barely reaching the laser (which I think would give the lowest length) so I can work out l2.
Original post by mosaurlodon
Ok I think I get what the question is asking?
So the time taken for the first pendulum to complete a half period is 0.3s so I can work out l1.
In this time the second pendulum completes a quarter period barely reaching the laser (which I think would give the lowest length) so I can work out l2.
So the time taken for the first pendulum to complete a half period is 0.3s so I can work out l1.
In this time the second pendulum completes a quarter period barely reaching the laser (which I think would give the lowest length) so I can work out l2.
Oh It just clicked! Thank you!
Original post by mosaurlodon
Oh It just clicked! Thank you!
I am still confused what is exact answer of total minimum length
Original post by mosaurlodon
Oh It just clicked! Thank you!
what is answer
If you post your working I can try to point you in the right direction
Quick Reply
Related discussions
- The cavendish experiment Isaac physics
- Make it More Brain-ey !!
- Physics A Level unit 4 questions
- SHM
- Circular motion
- Derivation of T = 2π√(l/g)
- FM-m2-circular motion
- AQA A Level Physics Paper 1 7408/1 - 26 May 2022 [Exam Chat]
- AQA A-level Further Mathematics Paper 3 Mechanics (7367/3M) - 14 June 2023
- a level chemistry aqa
- shape of molecules a level chem
- Gap year
- Nucelophiles Vs Ligands
- UCAT Medentry DM Question
- A level chem dipole question help needed!
- Make it More Time-ey !!
- Square pyramidal A level Chemistry
- Physics a level/as
- Will the bond angle in H2O(104.5) increase if water is bind to other molecules?
- To anyone who has used au pair world before
