Edexcel Mechanics A level question - Mock set 3

Using F=ma
If (3t-1)i + 2j = 0.5a
what does a = and hence what does the integral of a i.e. v =
and can anyone confirm whether the working in the mark scheme is correct

(edited 1 year ago)

Reply 1

mqb2766

Original post by gdunne42

Using F=ma
If (3t-1)i + 2j = 0.5a
what does a = and hence what does the integral of a i.e. v =
and can anyone confirm whether the working in the mark scheme is correct

Which question is it, can you post it / the ms?

Assuming its Q2, the velocity 9i+7j looks ok to me

(edited 1 year ago)

Reply 2

gdunne42

Original post by mqb2766

Which question is it, can you post it / the ms?

Here is the question

Mark scheme says v= (3t^2-2t)i + 4tj +C

Scan 30 Mar 2023.pdf308.2KB

Reply 3

mqb2766

Original post by gdunne42

Here is the question

Mark scheme says v= (3t^2-2t)i + 4tj +C

Thanks Id found it. The answer looks ok to me.

Reply 4

gdunne42

Original post by mqb2766

Thanks Id found it. The answer looks ok to me.

If (3t-1)i + 2j = 0.5a
Doesn't a = (6t-2)i + 4j

Reply 5

tiny hobbit

Original post by gdunne42

Using F=ma
If (3t-1)i + 2j = 0.5a
what does a = and hence what does the integral of a i.e. v =
and can anyone confirm whether the working in the mark scheme is correct

I agree with the mark scheme. a=(6t-2)i + 4j so v = (3t^2-2t + c)i + (4t + d)j and we have the initial velocity for finding c and d.

Reply 6

mqb2766

Original post by gdunne42

If (3t-1)i + 2j = 0.5a
Doesn't a = (6t-2)i + 4j

yes, then integrate that

Reply 7

gdunne42

Original post by tiny hobbit

I agree with the mark scheme. a=(6t-2)i + 4j so v = (3t^2-2t + c)i + (4t + d)j and we have the initial velocity for finding c and d.

Thank you. I can see where my working was flawed.

Reply 8

beyzacan

Original post by gdunne42

Using F=ma
If (3t-1)i + 2j = 0.5a
what does a = and hence what does the integral of a i.e. v =
and can anyone confirm whether the working in the mark scheme is correct