Question

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

Answer 1

Hi! Let's see.

TOPIC: Kinetic Energy.

Explanation:

Data:

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

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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 945 Joules.

Cordially Alejanndraax. Greetings!