00:01
For part a, we would like to find what is the magnitude of the impulse.
00:08
So to find our magnitude of our impulse, we can use our law of cosines to find our delta v squared.
00:17
So we have c squared is equal to a squared plus b squared minus 2ab cosine theta.
00:24
So that's what we want to plug in to find our delta v.
00:31
Okay, so now we want to plug in delta.
00:35
V squared is equal to first the speed which is 15 .80 so we have 15 .80 squared plus 15 .80 squared minus 2 15 .80 times 15 .80 times 15 .80 times cosine of that angle 33 degrees.
01:05
Okay so now we want to find what our delta v squared is.
01:10
So let's plug this into a calculator.
01:12
We have 15 .8 squared minus 15 .8 squared minus 2 times 15 .8 times 15 .8 times 15 .8 times cosine of 33 degrees, which is negative 418 .7.
01:33
Or this cosine of 33 degrees times 15 .8 times our 15 .8 times our 15 .8 times cosine of 33 degrees.
01:54
And so now we get from this expression, i want to make sure to plug it 2 in, okay? and so that should be our delta v squared.
02:12
So now we want to find just v squared.
02:15
So we then just take the square root of this expression...