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Question on kinetic energy down an inclined slope

Hello everyone!
I have been trying to solve this problem for quite some time but with little success. I cannot even seem to find the correct answer and my Mid-Terms are coming up. I figured you guys can help me out with this:

http://physics.dalzielhigh.org.uk/Physics/Unit_1_Higher_links_files/Componant%20of%20weight%20SQA%20question.pdf

Basically, I am unable to solve part c) but the rest is pretty simple. I would really appreciate a solution and explanation to this question.
Reply 1
So u have the acceleration, the initial velocity and the displacement. U can use a suvat equation to find the final speed, then u can sub this into ur kinetic energy formula

Hope i helped bro👊🏾
(edited 6 years ago)
Original post by Shaanv
So u have the acceleration, the initial velocity and the displacement. U can use a suvat equation to find the final speed, then u can sub this into ur kinetic energy formula

Hope i helped bro👊🏾


Ah! I see, that makes perfect sense. Can't believe I ignored those formulas. Really appreciate the quick help, mate. And you definitely helped :biggrin:
Reply 3
Original post by UsedCarSalesman
Ah! I see, that makes perfect sense. Can't believe I ignored those formulas. Really appreciate the quick help, mate. And you definitely helped :biggrin:


Glad to hear it good luck in ur mid terms
the KE at A is increased by the loss of GPE at B, but it is also decreased by the work against the frictional force.

KE at A = .5x2600x52 J

GPE loss = 2600x 9.8x 75xsin12

work done = 75 x 1400
(edited 6 years ago)
Original post by Shaanv
Glad to hear it good luck in ur mid terms


Thanks man! My first exam and hopefully it goes well. Quick question, a = 1.5 m/s^2 right? Because I feel like the acceleration changes so it won't be that.
(edited 6 years ago)
Reply 6
Original post by UsedCarSalesman
Thanks man! My first exam and hopefully it goes well. Quick question, a = 1.5 m/s^2 right? Because I feel like the acceleration changes so it won't be that.


The acceleration will be the value u have calculated as the forces remain constant, i havent done the math but ur answer to part b will be the constant acceleration of the van.

The bear working out also works, but if u have never encountered conservation of energy in that form before, then this method is not for u
(edited 6 years ago)
Original post by the bear
the KE at A is increased by the loss of GPE at B, but it is also decreased by the work against the frictional force.

KE at A = .5x2600x5 J

GPE loss = 2600x 9.8x 75xsin12

work done = 75 x 1400


While I understand what you are stating, I am unable to follow up on getting the final answer. Apologies for I am unfamiliar with their relation to work done. What do you suggest is the final answer?
Anyways, I really appreciate the help! :h:
The other method seemed easier but I feel like I should use two to confirm my answer.
i get 325225 J
Reply 9
The working out for the bear method

(edited 6 years ago)

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