(i) Distinguish between work, energy and power. State the SI units for each of these quantities.
(ii) A dog of mass 16 kg is running at a constant speed of 12 ms"1
Calculate the kinetic energy of the dog.
Share
(i) Distinguish between work, energy and power. State the SI units for each of these quantities.
(ii) A dog of mass 16 kg is running at a constant speed of 12 ms"1
Calculate the kinetic energy of the dog.
Sign Up to our social questions and Answers Engine to ask questions, answer people’s questions, and connect with other people.
Login to our social questions & Answers Engine to ask questions answer people’s questions & connect with other people.
Verified answer
Hey friend !(i)
Work is said to be done when a force acts on a body and displaces it along a distance in the same direction of force.
Work done = Force(F) x displacement(s)
Its SI Unit is Joule (J).
It is a scalar quantity [ quantities that require only magnitude only ]
---------------------------
Energy is the capacity to do work .
Its SI Unit is the same as that of work ---> Joule (J)
It is also a scalar quantity
-----------------------------------
Power is the rate of transfer of energy.
Power = Energy / Time
OR
Power = Work done / Time
Its SI Unit is Watt(W)
It is also a scalar quantity
===========================================================
(ii)
Mass = m = 16 kg
Speed = v = 12 m/s
Kinetic energy = K.E = 1/2 mv²
= 1/2 × 16 × 12 ×12
= 8 × 12 ×12
= 1152 Joules