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3 years ago

Lauryn serves a volleyball with a mass of 2.1 kg. The ball leaves her hand with a speed of 30 m/s.

Physics

1 answer:

Naya [18.7K]3 years ago

8 0

Hi! Let's see.

<h3><u>TOPIC: Kinetic Energy.</u></h3>

Explanation:

Data:

Mass(m) = 2.1 kilograms
Speed(v) = 30 m/s
Kinetic Energy(Ek) = ?

==================================================================

Use the kinetic energy formula:

$\boxed{\boxed{\bold{E_{k}=\frac{m*(v)^{2}}{2}}}}$

Replace by the data:

$\boxed{E_{k}=\frac{2.1kg*(30\frac{m}{s})^{2}}{2}}}}}$

We multiply speed squared:

$\boxed{E_{k}=\frac{2.1kg*900\frac{m}{s}}{2}}}$

Multiply in the numerator, without forgetting the units:

$\boxed{E_{k}=\frac{1890J}{2}}}}$

Both numerator and denominador operations are divided:

$\boxed{\bold{E_{k}=945\ J}}$

Answer: The kinetic energy is <u>945 Joules.</u>

Cordially Alejanndraax. Greetings!

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