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3 years ago

A 2.45 g table tennis ball has the KE of 31.5 J. At what velocity is the tennis ball traveling?

Physics

2 answers:

MAVERICK [17]3 years ago

8 0

Answer:

160.35 m/s

Explanation:

Kinetic energy of a body depends on the mass (m) of the body and the speed (v) with it is moving. It is the energy possessed by body due to virtue of its motion.

K.E. = 0.5 m v²

It is given that, m = 2.45 g = 2.45 ×10⁻³ kg

K.E. = 31.5 J

$v = \sqrt{\frac{2K.E.}{m}} = \sqrt{2\times 31.5}{2.45 \times 10^{-3}}=160.35 m/s$

Thus, the tennis ball is moving with the velocity of 160.35 m/s.

Ket [755]3 years ago

3 0

KE =
$\frac{1}{2} mv {}^{2}$
Convert g in kg
Find v:
2KE = mv^2
v=√2KE/m
v=√2*31.5/0.00245
v=160 m/s

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1 year ago

What should be the spring constant k of a spring designed to bring a 1200 kg car to rest from a speed of 85 km/h so that the occ

borishaifa [10]

Answer:

k = 5178.8 N/m

Explanation:

As we know that spring mass system will oscillate at angular frequency given as

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$\omega = \sqrt{\frac{k}{1200}}$

now the maximum acceleration of the spring block system is at its maximum compression state which is given as

$a = \omega^2 A$

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v = 85 km/h

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3 years ago

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Answer:

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3 years ago

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xxMikexx [17]

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