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3 years ago

An object of 4 kg has a speed of 6 m/s and moves a distance of 8 m. What is its kinetic energy in joules.

Physics

1 answer:

11Alexandr11 [23.1K]3 years ago

3 0

Answer:

The answer to your question is Ke = 72 J

Explanation:

Kinetic energy depends on the speed of and object and its mass.

Data

mass = m = 4 kg

speed = v = 6 m/s

distance = d = 8 m

Kinetic energy = ke = ?

Formula

Ke = (1/2) mv²

Substitution

Ke = (1/2) (4)(6)²

Simplification

Ke = (1/2)(4)(36)

Ke = (1/2)(144)

Ke = 72 Joules

Result

Ke = 72 J

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Hello there!

I hope you and your family are staying safe and healthy during this unprecendented time.

A) What is the work done?

Answer: We need to use the formula

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$w=-(35)(20)$

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B) What is the work done on the cart by the gravitational force?

Alright, we know that the gravitional force is perpendicular to the diplacement. Therefore, we gonna use the following formula:

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C) What is the work done on the cart by the shopper?

This is the easier part, since we already know that the work done by the shopper is the same as the work done by the friction force

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