a) Forms of energy
• Kinetic energy
• Potential energy
• Mechanical energy
• Electrical energy
• Chemical energy
b) i) Work done = force * distance
=mass× gravity ×height
2000kg*10N/kg *3m
=60000J
ii) Power = workdone/time
= 60000J/6 sec
=10000W
c)Efficiency = work output/ work input * 100%
=10000/12500 *100%
=80%
joseph kieti answered the question on November 17, 2017 at 06:45
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