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Physics moment help

https://media.discordapp.net/attachments/725201606202884099/1096077231912128552/V3V3y.png
I don't get question (d)
Here are the answers:
https://media.discordapp.net/attachments/725201606202884099/1096077436510273597/q9cMz.png

Reply 1

c4ssiopeia_5

For part (c) you applied a force vertically down to lift the front wheels off the ground, meaning that the pivot would have been the rear (back) wheels, so the horizontal distance from point A to the pivot is only 0.1 m
However, or part (d) you would have needed to apply a force vertically upwards to lift the rear wheels off the ground, hence the pivot would have been the front wheels. Therefore, the horizontal distance from point A to the pivot would then be 1.0 m (0.1 + 0.4 + 0.5). Hence, you would need a smaller force to lift the rear wheels as you know that moments = force x distance

It may be easier to draw a line diagram of this (with all the forces acting on it and the forces you may apply) so the shape of the object doesn't confuse you and then take moments about the specific pivot. Even if the questions say 'without further calculations', if you are really stuck, try doing the calculations to make sense of what the answer may be.