(a) What is the average useful power output of a person who does 6.00×106 J of useful work in 8.00 h? (b) Working at this rate,
1 answer:
Answer:
(a) 208.33 J/s
(b) 141.12 s
Explanation:
(a) Energy is the rate of doing work.
Work is the product of power and time
Work = Power × Time
Power = Work/time
where work is in joule and time is in seconds
Given that work = 6 ×
Time = 8 h = 8 × 60 × 60
= 28800 seconds
Average useful power =
= 208.33 J/s
(b) Given
mass = 2000kg , using g = 9.8 m/s2
Force = 2000 × 9.8
= 19600N
Work = Force × Distance ( considering that Work done to lift his body can be omitted because it is not considered useful output here)
Work = 19600 × 1.5
= 29,400J
Time taken = Work/Power
=
= 141.12s
≈ 2 Minutes 21 Seconds
At the rate of 208.33J/s, it will take the person 141.12 seconds to lift 2000 kg of bricks 1.50 m to a platform.
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Answer:
C. Inside its PPC
Explanation:
The Production possibility Curve also known as Production Possibility Frontier PPF is the curve that depict the relationship in the production of 2 given goods in an economy (See Image).
The curve basically shows 5 situations:
1. Point A: where all the production is devoted to Wheat
2. Point B: where all the production is devoted to Cotton
3. Points C: Any given point along the curve different to point A and B represent the trade off in the production of the 2 goods
4. Point D: Is an impossible point to achieve as it is outside the capabilities of the curve
5. Point E: Is an inefficient point of production as it is below the possibilities of production.
In the case of the expantion of the production capacity while the total spending fails to rise as fast. Then, the economy ends up in point E were inefficiency must be solve in order to produce in a maximum capacity.
