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1 vote
A box with a mass of 25 kg is lifted to a height of 3 meters in 2 seconds. How much work was done?

Group of answer choices

735 J

958 J

245 J

75 J

User Romel
by
6.9k points

2 Answers

4 votes

Answer:

735 J

Step-by-step explanation:

F (force) = ma = mg = 25kg × 9.81m/s² = 245.25N.

we are lifting, so the acceleration is going against Earth's gravity.

the work done to lift it up by 3 m is then

W = F×d = 245.25N×3 m = 735.75 J

the time (2 seconds) does not play a role here.

it would be needed to calculate the power needed to lift 25kg 3 m in 2 seconds :

power = W/t = 735.75/2 = 367.875 watts

User Arvin
by
6.3k points
5 votes

Answer:

Step-by-step explanation:

Work done = force x displacement

force = mass x acceleration (due to gravity)

work done =25 * 9.8 * 3 = 735J

User Maxime Schoeni
by
6.2k points