Chapter 4, Problem 85GP

(a)

To determine

To find: The weight of a fish can the fisherman land with constant speed.

Answer to Problem 85GP

  $10lb$

Explanation of Solution

Given Data:

  $\begin{array}{l}The\text{ fish is being pulled with constant speed}\text{.}\\ \text{i}\text{.e}\text{., a = 0}\end{array}$

Formula Used:

  $\text{T – mg = ma}$

Calculation:

  $\begin{array}{l}\text{Substituting the given value}\\ \text{T – mg = 0}\\ \text{i}\text{.e}\text{., T = mg = 45 N}\\ OrT=10\text{ lb}\end{array}$

Conclusion:

Therefore fisherman can land a fish of weight 10 lb safely.

(b)

To determine

To find: Maximum weight fish can be land if acceleration is 2.0 m/s² in upward direction.

Answer to Problem 85GP

  $8.3\text{ lb}$

Explanation of Solution

Given Data:

  $\begin{array}{l}Acceleration\text{ in the upward direction is 2}{\text{.0 m/s}}^2\\ i.e.,\text{ a = 2}{\text{.0 m/s}}^2,\text{ T = 45 N}\\ \text{1 lb = 4}\text{.45 N}\end{array}$

Formula Used:

  $T-mg=ma$

Calculation:

  $\begin{array}{l}\text{Substituting the given value}\\ \text{45 = m}\left(10+2\right)\\ m=\frac{45}{12}\text{ kg}\\ \text{Or m = }\frac{45}{12}\times \frac{100}{45}lb\\ \text{i}\text{.e}\text{., m = 8}\text{.3 lb}\end{array}$

Conclusion:

Therefore fisherman can land a fish of relatively lesser weight.

(c)

To determine

To find: Whether a trait of 15lb can be landed or not.

Explanation of Solution

Mass of trout is $15\text{lb}$ . It is not possible to hold a $15\text{lb}$ trout (fish) using a $10\text{lb}$ fishing line. If the fish is reeled in while still in the water, then a net used to remove the fish from the water.

Conclusion:

Therefore, a trout of more weight than the fishing line can be landed safely.