A 0.75 kg fish looking to strike at its prey accelerates from rest to 2 m/s in 0.25 second. If the average drag force from the water is 1.50 N, what is the forward force on the fish (that is the thrust that the tail fin makes when it pushes on the water)?

7.5 N

Explanation:

Given that a 0.75 kg fish looking to strike at its prey accelerates from rest to 2 m/s in 0.25 second. If the average drag force from the water is 1.50 N, what is the forward force on the fish (that is the thrust that the tail fin makes when it pushes on the water)?

Solution.

Since it accelerates from rest, initial velocity will be equal to zero.

Acceleration = velocity/time

Acceleration = 2 / 0.25

Acceleration = 8 m/s

Net force = mass × acceleration

F - 1.5 = 0.75 × 8

Where F = forward force of the fish.

F - 1.5 = 6

F = 6 + 1.5

F = 7.5N

Therefore, the force force on the fish is 7.5N.

  distance on the y-axis and time on the x-axis.

explanation:

the instantaneous velocity = change in position/time taken

the slope of the graph should give instantaneous velocity.

  slope of a graph = change in value of y -axis / change in values of x -axis

  comparing both the equations

    change in value of y -axis = change in position

  change in values of x -axis = time taken

so position values should be on the y axis and time values should be on the x axis.

distance on the y-axis and time on the x-axis.