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A meter stick is being balanced on a triangular piece of wood, with two blocks hanging off of it, a block with a weight of 5.9 N is hanging 14 cm to the left of the pivot, and there is another block with an Unknown weight hanging 35 cm to the right of the pivot. What is the Unknown weight?

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Answer:

Step-by-step explanation:

To find the weight of the unknown block, you can use the principle of moments, which states that the sum of the clockwise moments about a pivot point is equal to the sum of the anticlockwise moments about the same point 1.

The pivot point is the point where the meter stick is balanced. I'll first state that the weight of the unknown block is W N. The clockwise moment due to the 5.9 N block is:

clockwise moment = (weight of 5.9 N block) × (distance to pivot)

= (5.9 N) × (14 cm)

= 82.6 N·cm

The anticlockwise moment due to the unknown block is:

anticlockwise moment = (weight of unknown block) × (distance to pivot)

= (W N) × (35 cm)

= 35W N·cm

Since the meter stick is balanced, the clockwise moment must equal the anticlockwise moment. So now you can write,

82.6 N·cm = 35W N·cm

Then solve for W, and you'll get:

W = 82.6 N·cm / 35 cm

= 2.36 N

The weight of the unknown block is 2.36 N

User Mark Rowe
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