Advertisements
Advertisements
Question
How fast should a boy weighting 30 kg run so that his kinetic energy is 375 joule?
Advertisements
Solution
We know that , K.E = `1/2` mv2
375 = `1/2` x 30 x v2
or v2 = `(375 xx 2)/30` = 25 m/s
or v = 5 m/s
APPEARS IN
RELATED QUESTIONS
The S.I. unit of energy is .............
Give reasons for the following. No work is done if a man is pushing against a wall.
A person of mass 50 kg climbs a tower of height 72 metres. Calculate the work done. (g = 9.8 m s−2).
A girl is carrying a school bag of 3 kg mass on her back and moves 200 m on a levelled road. If the value of g be 10 m/s2, the work done by the girl against the gravitational force will be :
Define Translational motion.
A bucketful of water is to be drawn from a well ______ will be done when a ______ is applied to do this because there will be a ______ of water.
(displacement, work, force)
Write the two main conditions are needed for work to be done?
