dont know it
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8. A 0.1 kg inflatable ball floats on the surface of the sea. The current from the water underneath the ball exerts a force C=(2,1)N on the ball and the wind exerts a force of W = (3,-2) N on the ball.

(a) Find the resultant force exerted on the ball.

The question is Q8 of the mechanics section on this link: https://www.savemyexams.co.uk/wp-con...-Mechanics.pdf

The mark scheme says we just add C and W to get the resultant force but what about the weight of the ball?
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ghostwalker
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(Original post by dont know it)
8. A 0.1 kg inflatable ball floats on the surface of the sea. The current from the water underneath the ball exerts a force C=(2,1)N on the ball and the wind exerts a force of W = (3,-2) N on the ball.

(a) Find the resultant force exerted on the ball.

The question is Q8 of the mechanics section on this link: https://www.savemyexams.co.uk/wp-con...-Mechanics.pdf

The mark scheme says we just add C and W to get the resultant force but what about the weight of the ball?
The ball is floating. So, weight of ball equals upthrust due to water displacement, and they cancel each other out, i.e. are equal and opposite.

The other two forces are C and W which act on the horizontal plane.
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dont know it
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(Original post by ghostwalker)
The ball is floating. So, weight of ball equals upthrust due to water displacement, and they cancel each other out, i.e. are equal and opposite.

The other two forces are C and W which act on the horizontal plane.
Oh thanks.
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