A 2.2 kg otter starts from rest at the top of a muddy incline 93.9 cm long and slides down to the bottom in 0.60 s.

What net external force acts on the otter along the incline?

Does anyone know how to do this?

5 answers

gravity acts on the otter, and friction acts on the otter.
But the question requires a number answer. What should I do for that?
s=at²/2
a=2s/t²=2•0.939/0.6²=5.22 m/s²
F=ma=2.2•5.22=11.484 N
A 2.4 kg otter starts from rest at the top of a
muddy incline 94.9 cm long and slides down
to the bottom in 0.60 s.
What net external force acts on the otter
along the incline?
Answer in units of N.
It's 11.77N