Question

(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.

Answer 1

second question answer is

DATA:

m=16kg
v=12m/s

SOLUTION

formula using
k=1/2mv ^2
= 1/2 (16)(12)^2

k =1152joule.

first question answer is

ENERGY: the rate of doing work or transfering energy in or out of a system.

si unit : joule

types: kinetic energy and potential energy.

WORK: the force acting on a body while the body under goes a displacement.

it is a scalar quantity.

Units: it's unit is the unit of force multiplied by the unit of distance. in si Unit the unit of work is Newton -meter

1joule =1newton meter.

POWER: the rate of doing work .

P= amount of workdone/ time.
Unit : si Unit of power is watt .

1j/s = 1watt.

hope it will help you ☺

Answer 2

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 ]

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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  
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(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