00:01
You have a piano at the top of a ramp, it's going to be set in motion from rest.
00:06
So, v .i is equal to zero.
00:09
And you're asked to find how much time it will take to make it to the bottom of the ramp.
00:14
The total displacement down the ramp has to be found using some trig.
00:18
I know the opposite of the 20 -degree incline angle is one meter, and i'm looking for the hypotenuse.
00:25
So i can say that the sign of 20 degrees is equal to 1.
00:31
Over the displacement d, should be this length here.
00:36
Or d is equal to 1 over sign of 20.
00:43
If you solve that, you get 2 .9 meters.
00:55
So that's going to be d.
00:57
And i also have to get the acceleration.
00:59
The acceleration parallel to the ramp from the book is g sine theta.
01:05
And so a is equal to 9 .8 sine of 20 degrees.
01:09
You solve that and you get an answer of 3 .4 meters per second squared...