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Kinematics

A Motorcyclist travels on a straight road with a constant acceleration of 0.6 ms^-2
P and Q are two points on the road 120m apart. Given that the motorcyclist increases speed by 6 ms^-1 between these two points as she travels from P to Q find:
a) The time taken to travel from P to Q

Somebody help with this question.
Which suvat may be appropriate here (write down clearly what youre given).
I think S=ut + 1/2at^2
S=120 , U=6 , A=0.6 , t= ? Is that correct?
(edited 1 year ago)
Original post by Josephbrian
I think S=ut + 1/2at^2
S=120 , U=6 , A=0.6 , t= ? Is that correct?

You dont know u, as youre told the velocity increases by 6m/s over that time, so it cant be that one. Think about which suvats involve acceleration and time and whether you know the other "two" things.
Original post by mqb2766
You dont know u, as youre told the velocity increases by 6m/s over that time, so it cant be that one. Think about which suvats involve acceleration and time and whether you know the other "two" things.

S=vt - 1/2at^2. Or v=u + at that’s if u is 0. So which is it and what are the values for suvat?
Original post by Josephbrian
S=vt - 1/2at^2. Or v=u + at that’s if u is 0. So which is it and what are the values for suvat?

Id rearrrange v=u+at and note that 6 is the change in velocity so ...
Original post by mqb2766
Id rearrrange v=u+at and note that 6 is the change in velocity so ...

Is it like this 6=0+0.6*t to get 10s ? What is ur answer for question?
Original post by Josephbrian
Is it like this 6=0+0.6*t to get 10s ? What is ur answer for question?

Yes, though its incorrect to assume u=0. You should really just write it down as the definition of (constant) acceleration is
acceleration = change in velocity / change in time
so
0.6 = 6/t
The v=u+at is the basic gcse suvat which wraps that up.
(edited 1 year ago)
Original post by mqb2766
Yes, though its incorrect to assume u=0. You should really just write it down as the definition of (constant) acceleration is
acceleration = change in velocity / change in time
so
0.6 = 6/t
The v=u+at is the basic gcse suvat which wraps that up.

Wow thanks, idk why it’s a 5 mark question just for that.

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