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3 years ago

15

Using 1000 j of work, a toy elevator is raised from the ground floor to the second floor in 20 s. how much power does the elevat

or use?

1 answer:

Anastasy [175]3 years ago

3 0

Power (watts) = work done (joules) ÷ time (seconds)

power (watts) = 1000J ÷ 20s

power (watts) = 50w

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Answer:

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Explanation:

m = Mass of object = 70 kg

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Kinetic energy is given by

$\dfrac{1}{2}mv^2=2500\\\Rightarrow v^2=\dfrac{2\times 2500}{70}$

From conservation of energy we get kinetic energy equal to potential energy.

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4 years ago

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3 years ago

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s2008m [1.1K]

Answer:

the answers, the correct one is A v= 22.5 m/s

Explanation:

We can solve this problem using the concepts of conservation of mechanical energy

Starting point. Lowest point of the trajectory

Em₀ = K = ½ m v₀²

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let's calculate

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3 years ago