00:01
Okay, we are talking about a music cart, right? and i've tried to draw the diagram here.
00:06
We've got a bunch of information.
00:07
Our first order of business is to determine the velocity of the cart at a.
00:14
Okay, so let's see if we can do that.
00:17
So this will be potential energy plus the kinetic energy equals the potential energy plus the kinetic energy.
00:34
So here this will be zero plus mgh, and that will equal one -half.
00:56
Mv squared a.
01:00
So solving for a will get 2gh.
01:09
So my velocity at a will equal the square root of 2 times 9 .8 meters per second squared times my height was 120 meters, which will equal 48 .5 meters per second.
01:34
Okay, b, fine, let's switch colors reaction force.
01:51
Seat of the cart on the passenger at point b, which was up here in the top.
02:13
Okay, this is a little harder.
02:15
So let's think about this, our forces.
02:17
We'll have our normal force.
02:29
So n will equal m.
02:39
Okay, so let's figure out what her speed will be.
02:44
Let's get our v, and that will equal...