# The Kinetic energy of a moving object varies jointly with its mass m and the square of its velocity v. If an object weighting 90 kg and moving with avelocity of 20 m/s has a kinetic energy of 4500J, find its kinetic energy when the velocity is 32 m/s

2
by nimnimdelapena

• Brainly User
2016-05-13T13:19:00+08:00
Variation Equation:

KE = (k) (m) (v)²      where k is constant

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thank you so much
2016-05-13T13:30:04+08:00

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The formula for Kinetic Energy is KE= k(mv^2)/2,
where k is the proportionality constant,
m is the mass in kg,
v is the velocity in m/s.

By using the first set of data, we get:
4500=k (90 x 20^2)/2
which gives k a value of 0.25.

For the second set of data, we use the same formula:
KE = k(mv^2)/2
KE = 0.25 (90x32^2)/2

Finally, we get the value KE = 11, 520 J.

*note that J = (kg m^2)/s^2

thank you so much