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vaieri [72.5K]
2 years ago
8

As a boy pulls a sled carrying his sister, he exerts a force of 2.6 lbs.at an angle of 30 degrees with the ground. How much work

does he do if he pulls her at a constant speed for exactly one-half mile (2640 ft)?
Physics
1 answer:
kolezko [41]2 years ago
5 0

The amount of work done by the boy in pulling the sled is 8064.41 J

<h3>Definition of work done </h3>

Workdone is defined as the product of force and distance moved in the direction of the force. It can be expressed mathematically as:

Workdone (Wd) = force (F) × distance (d)

Wd = Fd

Considering angle projection,

Wd = FdCosθ

<h3>How to determine the workdone </h3>
  • Force (F) = 2.6 lb = 2.6 × 4.448 = 11.5648 N
  • Distance (d) = 2640 ft = 2640 × 0.305 = 805.2 m
  • Angle (θ) = 30°
  • Workdone (Wd) =?

Wd = FdCosθ

Wd = 11.5648 × 805.2 × Cos 30

Wd = 8064.41 J

Learn more about workdone:

brainly.com/question/14667371

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