Answer:
W = 2747,1 [J]
Step-by-step explanation:
Chain is 64 meters long with mass 24 Kg
Then weight of the chain is p = 24 * 9.8
p = 235.2 [N] N = kg*m/s²
And by meter is 235,2 / 64 = 3.675
Total work has two component
- work to lift the 13 top meters of chain W₁
W₁ = ∫₀ᵇ F(y) dy
- work to lift last ( 64 - 13 ) meters 51 W₂
W₂ = 3.675 * 51 * 13 Kg m² /s² [J]
W₂ = 2436,53 [J]
We need to calculate W₁
W₁ = ∫¹³₀ mgy dy ⇒ W₁ = ∫¹³₀ 3,675 ydy
W₁ = 3,675* ∫¹³₀ ydy W₁ = 3,675* y²/2 |₀¹³
W₁ = 3,675* 84,5 [J]
W₁ = 310,54 [J]
And total work W
W = W₁ + W₂
W = 310,54 + 2436,53 [J]
W = 2747,1 [J]
The top one. Think about the difference between each one: X goes from 1 to 2 and Y goes from 5 to 10. Each number you go up, Y increases by 5. This means there is a proportional relationship.
If we have 2 more blue pens than black pens, our blue pens can be rewritten as blue = 2 + black. Now we can set up an equation. Originally this equation would involve both blue and black, but since we only have 1 equation to set up, we can only have 1 unknown. That's why we base the number of blue pens on the number of black pens and do a substitution. So instead of blue + black = 94, we have (black + 2) + black = 94. That simplifies to 2 black + 2 = 94, and 2 black = 92. Now if we divide by 2, we get that the number of black pens is 46. If we have 2 more blue than black, the number of blue pens we have is 48. 46 + 48 = 94, so there you go!
The answer is Strong Positive