Spring Pick-up
https://isaacphysics.org/questions/spring_pick_up_num?stage=a_level
For this part a of this q, I got the answer using the change frame of reference way, but I wanted to do it using the video way where you set up equations like this video: https://youtu.be/r9UY3F5Drog and then solve.
But im not really seeing a way through to get to the answer - if anyone could help with what im doing wrong it would be greatly appreciated.
For this part a of this q, I got the answer using the change frame of reference way, but I wanted to do it using the video way where you set up equations like this video: https://youtu.be/r9UY3F5Drog and then solve.
But im not really seeing a way through to get to the answer - if anyone could help with what im doing wrong it would be greatly appreciated.
Working:
I tried to do it by using a substitution of z = x2 - x1 = Acos(wt+phi) for the first half of my working to see if that would work but just ended up with Aw, which I dont know the values of... and then went back to the video way
And just for compact notation I represented the integral of x1 wrt time as x1_underdot - sorry if thats confusing to understand
I tried to do it by using a substitution of z = x2 - x1 = Acos(wt+phi) for the first half of my working to see if that would work but just ended up with Aw, which I dont know the values of... and then went back to the video way
And just for compact notation I represented the integral of x1 wrt time as x1_underdot - sorry if thats confusing to understand
(edited 8 months ago)
Original post by mosaurlodon
Working:
I tried to do it by using a substitution of z = x2 - x1 = Acos(wt+phi) for the first half of my working to see if that would work but just ended up with Aw, which I dont know the values of... and then went back to the video wayAnd just for compact notation I represented the integral of x1 wrt time as x1_underdot - sorry if thats confusing to understand
I tried to do it by using a substitution of z = x2 - x1 = Acos(wt+phi) for the first half of my working to see if that would work but just ended up with Aw, which I dont know the values of... and then went back to the video way
You seem to be throwing a few ideas together and hoping, but starting from scratch youd have (mass position x and block ut+l, where the mass and the block are seperated by the natural length at the start). Then
mx'' = k(ut-x)
with initial conditions 0,0. So sub the extension z = ut-x and solve the ode as normal, noting the transformed initial conditions for z, or solve the inhogeneous equation in x (looks more laborious). In either case, the initial conditions are important.
Must admit, I dont understand where they suggest integrating to get velocity, ...
(edited 8 months ago)
throwing a few ideas together and hoping is my optimal strategy
initial conditions - Yup thats what I was missing
so you get at t=0, z' = -Aw = u and so x'_max = 2u
Id like to think I was close with my original working... but looking back not really
Anyways thank you
initial conditions - Yup thats what I was missing
so you get at t=0, z' = -Aw = u and so x'_max = 2u
Id like to think I was close with my original working... but looking back not really
Anyways thank you
Original post by mosaurlodon
throwing a few ideas together and hoping is my optimal strategy
initial conditions - Yup thats what I was missing
so you get at t=0, z' = -Aw = u and so x'_max = 2u
Id like to think I was close with my original working... but looking back not really
Anyways thank you
initial conditions - Yup thats what I was missing
so you get at t=0, z' = -Aw = u and so x'_max = 2u
Id like to think I was close with my original working... but looking back not really
Anyways thank you
You seemed 1/2 way there, but leaving out the ICs means youre fiddling with phi etc and really you just want to say
z = Asin(wt)
and it all falls out from there.
Quick Reply
Related discussions
- Spring Pick-up
- Am I disadvantaged for Summer internship applications?
- Architecture at uni
- Applying for student finance in march before accommodation?
- Enhancing my Personal Statement for Mechanical Engineering
- Messes up Year 12
- What should i study at Uni?
- What do you do with your Boxing Day?
- GCSE for medicine at Oxford
- Maths or Chemistry (HELP!)
- Physics IGCSE question Newton's Laws
- how many clothes do i bring to uni?
- It’s Spring/Easter on TSR! - 2025 Hub Thread
- Unsure on what 3rd A-level to choose??
- Is a Computer Science degree worth it?
- Everyday feels like hell
- QMUL (AAA) vs Exeter (ABB) for Investment Banking – Which Should I Pick?
- any a-level advice?
- University of Glasgow or Queen Mary University of london
- Gap Year Maths
Latest
Trending
Last reply 1 month ago
A level Edexcel physics aluminium foil passing through a uniform fieldPhysics
3
6
Last reply 1 month ago
If you could spin a hand spinner at the speed of light could it affect Space Time?Physics
6
5
Last reply 1 month ago
Using the equatorial diameter, how large is Mercury compared to Earth?Physics
2
3
