Physics Help ?!1?

Question

A fisherman in a boat is using a "10-lb test " fishing line. This means that the line can exert a force of 45 N without breaking.. (1lb=4.45N).

(A) How heavy a fish can the fisherman land if he pulls the fishup vertically at constant speed?

B: If he accelerates the fish upwards at 2.0 m/s^2 what maximum weight fish can he land?


Now i have no clue what to do in this. I am so lost. Im pretty sure this has to do with Newtons laws or soemthing. Any help would be awesome!

Answer 1

Weight is a force an object is experiencing when subjected to gravity.

a) W=10lb of fish or weight = 44.5 N

b)
F=ma
m= F/a= 44.5/ 2.0= 22.25 kg
Weight is
W= mg= 22.25 x 9.81=218 N

Answer 2

The acceleration of gravity is 9.81m/s^2.

Acceleration is the change in velocity, therefore if the velocity upwards is constant, then the only acceleration is due to gravity.
F=ma
45=m*9.81
m=45/9.81
m=4.59kg

If the fish is being pulled upwards at a 2 m/s^2 (opposite the 9.81m/s^2 downwards), then the equation looks like this:
F=ma
45=m*(9.81+2)
45=m*11.81
m=45/11.81
m=3.81kg