The kinetic energy of a 30.0 kg ball is 5.00 X 10^2 J. What is the speed of the ball?

2 Answers

justaguide's profile pic

justaguide | College Teacher | (Level 2) Distinguished Educator

Posted on

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The kinetic energy of a body with a mass m kg and moving at a speed v m/s is given by K.E. = (1/2)*m*v^2 J

The kinetic energy of the ball with a mass 30 kg is 500 J. If the speed of the ball is v, from the equation for kinetic energy given earlier we get:

500 = (1/2)*30*v^2

=> 1000/30 = v^2

=> v = sqrt (100/3)

=> v = 5.774 m/s

The speed of a 30 kg ball with a kinetic energy of 500 J is 5.774 m/s

sanjeev5757's profile pic

sanjeev5757 | High School Teacher | (Level 1) Honors

Posted on

kinetic energy E=1/2 M.V^2

Where M is mass of body.

    and V is velocity of body.

as given,M=30Kg.


Putting it to above formula-







Hence speed of ball is 5.77m/s.