00:01
So we're asked about an airplane traveling at a certain speed.
00:08
And so kinetic energy, our equation for kinetic energy, is one -half times m times velocity to the second power.
00:25
So kinetic energy is one -half.
00:31
The mass is 2 and 4 tenth.
00:38
This is given to us times 10 to the fifth power kilograms.
00:49
The velocity is 900 kilometers.
00:54
9 .00.
00:56
Now, i want to write that as meters, so i don't get confused.
00:59
And i'm going to write that over because it looks like there's a decimal point in there, but i did not intend a decimal point.
01:05
So 900, kilo times 10 to the third meters per hour.
01:25
And i just realized that i can't be putting in meters per hour because i need meters per second for the basic si units.
01:38
So 900 times 10 to the third power meters per hour.
01:46
And there are 3 ,600 seconds in an hour.
01:52
So 3 ,600 seconds in one hour.
02:01
Um, hour.
02:04
Okay.
02:06
I guess i could have written h for that.
02:10
So i'm going to take 900 times 10 to the third power, 900 times 10 to the third power, and i'm going to divide by 3 ,600.
02:23
So i have the basic units.
02:28
That's going to give me 250.
02:34
And that's going to be meters per second.
02:38
So i need to go back up, erase what i wrote here because my units weren't right...