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Salsk061 [2.6K]

2 years ago

10

A lift travelling up to the top floor of the Empire State building with a mass of 4200kg and a kinetic energy of 4116J. find the

velocity
please helpp

1 answer:

Tomtit [17]2 years ago

6 0

Answer:

$v = 1.4 m/s$

(v= velocity)

Explanation:

Kinetic Energy is computed using the formula

$KE = \dfrac{1}{2}mv^2$

where m = mass of the object in kg and v is the velocity in m/s

Given KE = 4116J,
m = 4200 kg

Substitute and solve for v

$4116 = \dfrac{1}{2}4200\cdot v^2$

=> $4116 = 2100\cdot v^2$

$v^2 = \dfrac{4116}{2100}\\\\v^2 = 1.96\\\\v = \sqrt{1.96}\\\\v = 1.4 m/s$

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Answer:

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