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1. question is attached below

if you could describe what you did in detail that would be much appreciated.

thank you
2. (Original post by amin11234)
question is attached below

if you could describe what you did in detail that would be much appreciated.

thank you
3. (Original post by amin11234)
question is attached below

if you could describe what you did in detail that would be much appreciated.

thank you
Have you tried anything at all? The way in to part (i) is to determine the change in height for object A and the 5kg block associated with object D moving down by 1.5m. Then work out the change in gravitational potential energy for each object.

4. (Original post by old_engineer)
Have you tried anything at all? The way in to part (i) is to determine the change in height for object A and the 5kg block associated with object D moving down by 1.5m. Then work out the change in gravitational potential energy for each object.

Hello, for part (i) how would i find the change in height for object A and the 5kg block associated with object D moving down 1.5m?

After i find those out i just add the change in gravitation potential energy from all 3 parts. Then i can go onto part (ii) with mgh=1/2mv^2.

5. (Original post by amin11234)
Hello, for part (i) how would i find the change in height for object A and the 5kg block associated with object D moving down 1.5m?
You are told that the strings are inextensible, so you can infer that when object D falls by 1.5m, the 5kg block must move up the slope by 1.5m. The slope is incline at 40deg to the horizontal (given) so you just have to use basic trigonometry to determine the gain in height corresponding to a displacement up the slope of 1.5m.
6. (Original post by old_engineer)
You are told that the strings are inextensible, so you can infer that when object D falls by 1.5m, the 5kg block must move up the slope by 1.5m. The slope is incline at 40deg to the horizontal (given) so you just have to use basic trigonometry to determine the gain in height corresponding to a displacement up the slope of 1.5m.
Ok i get it, and object A also goes up 1.5m?
7. (Original post by amin11234)
Ok i get it, and object A also goes up 1.5m?
Yes
8. (Original post by old_engineer)
Yes
ok thanks, got it. i added the change in g.p.e of all 3 objects and got a total of 326.54 J.

but now i am stuck with part (ii) i have tried so many ways but i dont know how it hits the ground at 2.20 m/s.

ive tried suvat and k.e gained=p.e lost but i can never get 2.20 m/s. ive even tried adding all the resistance forces together but still not 2.20m/s.

can you give me some guidance on what i should do.

thank you.
9. (Original post by amin11234)
ok thanks, got it. i added the change in g.p.e of all 3 objects and got a total of 326.54 J.

but now i am stuck with part (ii) i have tried so many ways but i dont know how it hits the ground at 2.20 m/s.

ive tried suvat and k.e gained=p.e lost but i can never get 2.20 m/s. ive even tried adding all the resistance forces together but still not 2.20m/s.

can you give me some guidance on what i should do.

thank you.
You need to look again at part (i) as the change in GPE of object D is opposite in sign to that of object A and the block.

Then PE lost = KE gained + work done against friction. For this you should use your value of PE lost from part (i) and note that work is done against friction in two places - the block and object D.

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