<p>Hey not sure if anyone else saw it, but it was like number 68 or so.
the problem told the speed of a car mass 3.0x10^5 or something kg moving at 30m/s
then it said:"the speed of light is 3x10^8 m/s"
and then asked what the mass would be from the kinetic energy.</p>
<p>this question seemed so messed up and misworded to me.
anyone else see this problem?
or am i missing something lol</p>
<p>The car had a mass of 2.0x10^3 kg and was moving at a speed of 30m/s. Using the KE=1/2(mv^2) equation, we can get the total kinetic energy of the car
1/2<em>(2x10^3 kg)</em>(9x10^2 m^2/s^2) = 9x10^5 J. Now the question asked what would be the mass equivalent of the car having that as its REST energy. We use Einstein’s E=mc^2 equation and divide the kinetic energy by the c^2 (9.0x10^16 m^2/s^s) to get the mass:</p>
<p>(9x10^5 J)/(9x10^16 m^2/s^2) = 10^-11 kg.
The mass was 10^-11 kg.</p>
<p>thanks man, i see what i missed lol,
guess i blanked out towards the end</p>