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ValentinkaMS [17]

3 years ago

10

Zak, helping his mother rearrange the furniture in their living room, moves a 60 kg sofa 5.9 m with a constant force of 40 N. Wh

at is the work done by Zak on the sofa? Neglect friction. Answer in units of J

2 answers:

Valentin [98]3 years ago

5 0

Answer:

236 j

Explanation:

mass of sofa, m = 60 kg

distance, d = 5.9 m

force, F = 40 N

Work done is defined as the product of force applied on the body and the displacement in the position of the body in the direction of force.

W = F x d

W = 40 x 5.9

W = 236 J

Thus, the work done is 236 J.

Len [333]3 years ago

4 0

Answer:236 J

Explanation:

Given

Mass of sofa $m=60 kg$

Displacement $s=5.9 m$

Force $F=40 N$

neglecting Friction

Work done is given by

$W=F\cdot s$

$W=F\cdot s\cos 0$

$W=40\cdot 5.9$

$W=236 J$

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Answer:

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Answer:

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Let $\omega_2$ is the angular velocity when the person reaches the edge. We need to find it. It can be calculated using the conservation of angular momentum as :

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Answer:

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