u need to know the principle of moments.
doubt u hv covered it in Sec 1.
r u in some IP class doing advanced lvl such as Sec 3 Physics?

let's work with what u already know

do u see the 'pivot' in the diagram?

since u hv learnt Moment or just Lever, u merely know Load, Effort & Fulcrum? Or do u know the formula for moment:
moment = F x d ?

if u know the formula, then continue reading.


look at the link in the diagram, figure out the following:
1. What is the force in the link? let's call it F1
2. What is the perpendicular distance to this F1? let's call it d1
3. Can u calculate this Moment :
Moment = F1 x d1?


Next,
look at the pedal in the diagram, figure out the following:
1. What is the force by driver? let's call it F2
2. What is the perpendicular distance to this F2? let's call it d2
3. Can u calculate this Moment :
Moment = F2 x d2?

if u understand this so far,
Principle of Moments merely states that the two moments above are the one and the same.
hence, F1 x d1 = F2 x d2

got it?

if u read the ms properly,
this qn is not just a Moment qn.

there is a Pressure component in this qn.

so rightfully, this qn is considered a difficult qn, even for a IGCSE student.

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