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3 years ago

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Elias serves a volleyball at a velocity of 16 m/s. The mass of the volleyball is 0.27 kg. What is the height of the volleyball a

bove the gym floor if its total mechanical energy is 41.70 J? Round to the nearest tenth. m

1 answer:

liberstina [14]3 years ago

6 0

Answer:

The correct answer to the following question will be "2.7 m".

Explanation:

The given values are:

Velocity, v = 16 m/s

mass, m = 0.27 kg

Mechanical energy, M.E = 41.70 J

g = 9.8 m/s²

As we know,

Kinetic energy, $K=\frac{mv^2}{2}$

Potential energy, $U=m.g.h$

Now, the total mechanical energy will be:

⇒ $\frac{mv^2}{2}+U$

⇒ $41,71 \ kg.m^2/s^2$

Now,

⇒ $h=\frac{E-(\frac{mv^2}{2})}{mg}$

On putting the estimated values, we get

⇒ $=\frac{41.70-(\frac{0.27(16)^2}{2})}{0.27\times 9.8}$

⇒ $=\frac{41.70-(\frac{0.27\times 256}{2} )}{2.64}$

⇒ $=\frac{41.70-34.56}{2.64}$

⇒ $=\frac{7.14}{2.64}$

⇒ $=2.7 \ m$

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Explanation:

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