A certain man needed 400N of force to pull a load through a distance of 150cm in 8s . Calculatell i) the work done by man ii) the power developed by man

a) 600 J

b) 75 W

Explanation:

Force= 400 N, distance = 150 cm = 1.5 m, time= 8s

a) Work is the product of force acting on an object and distance (or displacement). The S.I unit of work is the joules.

Work = force × distance = 400 × 1.5 = 600 J

b) Power is the amount of energy transferred per unit time. It is the ratio of work to time. The S.I unit of power is watt

Power = work/time = 600 / 8 = 75 W

b. accuracy of the data matters alot more than its number of digits, organization or amount of detail. quantitative observation is more accepted than the qualitative observation.