The kinetic energy of a body moving with the speed of 10 ms-1 is 30 J. If its speed becomes 30 ms-1 then its K.E becomes:
Correct answer: C. 270 J
- A. 10J
- B. 90J
- C. 270 J
- D. 180 J
Explanation
The explanation for the question is: To calculate the kinetic energy of the body we use the equation K.E = 1/2mv2By given data we will calculate the mass of the body. Given that v1 = 10m/s, K.E= 30J so mass will bem= 2(K.E)/v2m= 0.6 Now, calculating K.E 2K.E 2 = 1/2 (0.6) (30)2K.E 2 = 270Jso, this option is right
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Work transfers energy when a force causes displacement, while kinetic energy, gravitational potential energy and power describe motion, position and the rate of energy transfer. The work-energy theorem links net work with change in kinetic energy, and efficiency accounts for energy losses rather than treating them as energy destruction.
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