Every second the sun converts about 600 million tons of...

Every second, the Sun converts about 600 million tons of hydrogen into 596 million tons of helium. The remaining 4 million tons of mass O is re-absorbed as molecular hydrogen O is ejected into space by solar flares O is converted to energy and transported to the Sun's surface O is ejected into space in a solar wind O disappears from the universe

Transcript

00:01 So in this problem, you're told that the luminosity of the sun is four times 10 to the 26th watts, which is the same thing as saying four times 10 to the 26th joules of energy is being released every second.

00:14 And we want to know how much mass does the sun change into energy every second? so the equation that relates energy and mass is kind of einstein's classic equation equals mc delta t.

00:29 And we're given our energy, we're going to try and solve for our mass.

00:32 And then the speed of light is actually a constant value.

00:35 It's 3 .0 times 10 to the 8 meters per second.

00:42 And then in order to kind of solve for a unit of mass, we're trying to solve for our mass in kilograms.

00:49 So we just need to rewrite the unit, the jewel.

00:53 So what a jewel equals, what a j is actually equal to, is kilograms times, meters squared over seconds squared.

01:03 So now we're ready to kind of plug in our values.

01:07 So we're looking at one second.

01:10 So in one second we get four times 10 to the 26th joules, or we can say kilograms times meter squared over seconds squared, equals the mass, which is what we're trying to solve for, times the speed of light, which is 3 .0 times 10 to the eighth.

01:29 Meters per second squared.

01:32 So first we're going to square our speed of light value.

01:37 So three squared is nine, 10 to the eighth squared is 10 to the 16th.

01:43 And then our units will be meters squared second squared.

01:48 This should be a multiplication sign.

01:50 Sorry about that.

01:53 So i get m by itself.

01:54 We're going to divide both sides of our equation by that value.

01:58 And i'm just kind of being thorough with the units to make sure we can see how they cancel out...