# Hi, could someone please give me a hand with question (b) in the image attached?

Hi Kieran

b) (i)
W=F x d
= (55x 10) x 25
= 13 750 J (or Nm. You can use Joules as the unit or Newton meters)
Note that for this question, “force” is calculated using Ariana’s mass multiplied by 10 (acceleration due to gravity)

I’m assuming you might need some help with (ii) as well?
This is from the 2022 paper.
ii) P = W/t
= 13 750 J / 120 s
= 114.58 W
= 110 W (2s.f) *
Note that rounding isn’t a requirement for this paper (if you had left your answer as 114.58 W, that would have also been acceptable.) However, it is always good practice in physics to round your final answer to an appropriate number of significant figures.

iii) To lower her power output she would have to increase the time she takes to climb up the hill. This is because the work she does to go up the hill remains the same. Since power is the amount of work done divided by the time taken (to carry out the work), taking a longer time will hence decrease her power.

Hope that helps!
Keep doing those questions !
Kia kaha

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Thank you so much for your help.