3 years ago

A mass of 2.1 kg the ball leaves her hand with the speed of 30 mass find the energy of the ball

Physics

1 answer:

snow_lady [41]3 years ago

8 0

Ke= 1/2 x m x v^2
Ke= 1/2 x 2.1 x 30^2
Energy = 945 J

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In a track and field event, a hammer thrower accelerates the hammer (mass = 7.30 kg) from rest within four full turns (revolutio

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Answer:

5.69755 rad/s²

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r = Radius = 1.3 m

v = Velocity of the hammer = 22 m/s

n = Number of revolutions = 4

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$\theta=n\times 2\pi\\\Rightarrow \theta=4\times 2\pi\\\Rightarrow \theta=8\pi$

$\omega_i$ = Initial angular speed = 0

Final angular speed

$\omega_f=\frac{v}{r}\\\Rightarrow \omega_f=\frac{22}{1.3}\\\Rightarrow \omega_f=16.92307\ rad/s$

Angular acceleration

$\alpha=\frac{\omega_f^2-\omega_i^2}{2\theta}\\\Rightarrow \alpha=\frac{16.92307^2-0^2}{2\times 8\pi}\\\Rightarrow \alpha=5.69755\ rad/s^2$

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3 years ago

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natali 33 [55]

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