00:01
Okay, a person is pushing horizontally on a box with a constant force.
00:04
So let's draw this situation.
00:09
So here's our box.
00:12
And the person is pushing with a constant force.
00:15
We'll just draw the force here.
00:17
I'll say it's to the right.
00:20
Causing it to slide with a constant speed.
00:23
So that's important, right? so the speed equals a constant, even 5 meters per second, actually.
00:35
They toss.
00:38
So if the speed is constant, what does that mean? well, if we sum all the forces on the box, that equals mass times acceleration.
00:50
If the speed is constant, acceleration is zero.
00:53
So the sum of the forces equal zero...