A seal swims rightward 3 m, but then notices a shark behind it. The seal speeds up rightward for 12 m and swims a total time 4 s.

3 m

12 m

What is the seal's average velocity for the swim?

2.25m/s

Explanation:

Average velocity is the change in displacement of a bod with respect to time;

Velocity = Δd/Δt

velocity = d₂-d₁/Δt

Given d₂ = 12m, d₁ = 3m and Δt = 4s

Substitute the given value into the fromula;

velocity = 12-3/4

velocity = 9/4

velocity = 2.25m/s

Hence the seal's average velocity for the swim is 2.25m/s

force is mass*acceleration.

we have a very small mass: 11.4*0.001 kg

if we want 0.035n of force, we need an acceleration:

0.035 = 11.4*0.001*a

a = 0.035/(11.4*0.001) m/s^2

increase masses, decrease separation