Physics-SCALLOP FORCE QUESTION

Question

Scallops eject water from their shells to provide a thrust force. The figure shows a smoothed graph of actual data for the initial motion of 25 g scallop speeding up to escape a predator.

1. What is the magnitude of the net force needed to achieve this motion?
2. How does this force compare to the 0.25 N weight of the scallop?

Figure...

At t=0.0 v=0.0

At t=0.1 v= 0.1

At t=0.2 v=0.2

Answer 1

First we find acceleration a using the graph and the formula

v = at

a = 1 m/s²

Now we can find the force

F = ma = 25 g * 1 m/s² = 0.025 N

F is 1/10 of the weight of the scallop