Question

How much mass is equivalent to 1MJ of energy? (1 MJ=1*10^6 J) (The mass energy equivalence equation and speed of light are given below.)

E=mc^2
C=3.0*10^8 m/s
A. 3.3 * 10^-3 kg
B. 1.1 * 10^-5 kg
C.1.1 * 10^-11kg
D.9.0*10^22kg

Answer 1

Energy - Mass equation is,
E = mC²

E = Energy ( unit is J)
m = Mass of the particle ( Unit is kg)
C = Speed / velocity of light ( unit is m s⁻¹) = 3.0 x 10⁸ m s⁻¹

by rearranging the equation,
m = E /C²
m = 1 x 10⁶ J / (3 x 10⁸)² m² S⁻²
m = 1.1 x 10⁻¹¹ kg

Hence the answer is "C".