Try it on paper first. A hint, the key idea and the worked solution are here when you need them.
A box slides from rest down a slope long, at to the horizontal. The coefficient of kinetic friction is . Taking , find its acceleration and its speed at the bottom.
On a slope at angle , split the weight: down the slope and into it, so . Sliding down a rough slope, friction acts up it:
A body at rest starts to slide when .
Have you tried it?
Work it out on paper first. It is fine to get stuck or make a mistake: that is how we learn. When you are ready, go through the solution one step at a time, and check each step against your own.
Given. , , , .
Plan. Find , then the speed from .
Step 1. Acceleration. .
Step 2. Speed. .
Answer: , and at the bottom.
Check. On a smooth slope, would be . Friction makes it smaller, as it should.
Watch out. Friction depends on , not on .
Log in to join the discussion.
Loading…