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A level physics mechanics question

Why are we equating the moments of T and F if they are both pulling clockwise?Screenshot 2024-05-07 at 20.26.23.png
Screenshot 2024-05-07 at 20.26.38.png
Screenshot 2024-05-07 at 20.32.36.png
(edited 1 month ago)
Reply 1
Original post by gcsestudent56
Why are we equating the moments of T and F if they are both pulling clockwise?Screenshot 2024-05-07 at 20.26.23.png
Screenshot 2024-05-07 at 20.26.38.png
Screenshot 2024-05-07 at 20.32.36.png

Its a lever so the aim is to gain a mechanical advantage by increasing the force. F is the force on the lever and T is the force on the ship.. An equal but opposite force to T would be being applied to the lever (force pair).
(edited 1 month ago)
Original post by mqb2766
Its a lever (not in equilibrium) so the aim is to gain a mechanical advantage by increasing the force. Also, F is the force on the lever, but T is the force on the ship. An equal but opposite force would be being applied to the lever.

im ngl i still don't get what any of that means
Reply 3
Original post by Gcsestudent56
im ngl i still don't get what any of that means

If you consider the lever, then the two forces being applied are F and -T. -T is anticlockwise.
Original post by mqb2766
If you consider the lever, then the two forces being applied are F and -T. -T is anticlockwise.

oh wait so if the lever is being pulled down by force F, there is going to be tension downwards as the boat weight is pulling it down. So that why we consider the tension to be anti clockwise? Might be waffling, sorry im awful at mechanics
Original post by mqb2766
Its a lever so the aim is to gain a mechanical advantage by increasing the force. F is the force on the lever and T is the force on the ship.. An equal but opposite force to T would be being applied to the lever (force pair).

Also I dont get the last sentence.
Reply 6
Original post by Gcsestudent56
oh wait so if the lever is being pulled down by force F, there is going to be tension downwards as the boat weight is pulling it down. So that why we consider the tension to be anti clockwise? Might be waffling, sorry im awful at mechanics

The lever is pulling the boat up (tension upwards) and the boat is pulling the lever downwards (tension downwards). In the diagram T is upwards so when you think about the lever, the relevant force is -T and its acting anticlockwise (on the lever).
Original post by mqb2766
The lever is pulling the boat up (tension upwards) and the boat is pulling the lever downwards (tension downwards). In the diagram T is upwards so when you think about the lever, the relevant force is -T and its acting anticlockwise (on the lever).

I get it now thanks. I really need to work on mechanics. Is there a specific youtuber that helped you learn mechanics? Cuz I really need help
Reply 8
Original post by Gcsestudent56
I get it now thanks. I really need to work on mechanics. Is there a specific youtuber that helped you learn mechanics? Cuz I really need help
Sorry, dont know. A fair bit of it is to try and follow the guidelines and make sure you understand the terms. So sketch force diagrams, make sure you only put on forces on the specific object, ...

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