Question

A quantity of energy equal to 8.90 × 1012 joules was emitted from a nuclear reaction. What amount of mass was required to be converted to yield this amount of energy?

9.90 × 10-5 kg

2.96 × 10-4 kg

2.67 × 104 kg

8.01 × 105 kg

Answer 1

Answer : The amount of mass required will be,
`9.90* 10^(-5)Kg`

Explanation :

The formula used for energy is :

`E=m* c^2`

where,

E = energy =
`8.90* 10^(12)J`

m = mass = ?

c = speed of light =
`3* 10^8m/s`

Now put all the given values in this formula, we get :

`8.90* 10^(12)J=m* (3* 10^8m/s)^2`

`m=9.90* 10^(-5)Kg`

Therefore, the amount of mass required will be,
`9.90* 10^(-5)Kg`

Answer 2

E = mc^2
E = 8.90 * 10^12 Joules
c = 3 * 10^8 m/s
m = ????

8.90 * 10^12 = m * (3 * 10^8)^2
8.90 * 10^12 = m * 9 * 10^16
9.889 * 10^-4 kg = m <<<<< answer