Question

Use Einstein’s energy equation to solve the following problem. Recall that the speed of light is 3 x 108 m/s. If a 5.0-kg stone is completely converted to energy, what is its energy equivalent in joules?

Answer 1

Its energy equivalent in Joules is

E = 4.5 × 10^17Joules

Step-by-step explanation:

The Einstein energy equation is expressed as shown

E = mc² where:

m is the mass of the stone

c is the speed of light

Given:

m = 5.0kg

c = 3 x 10^8 m/s

E = 5×(3 x 10^8)²

E = 5×(9×10^16)

E = 45 × 10^16

E = 4.5 × 10^17Joules

Answer 2

E =mc²

= (5.0-kg)(3 x 10^8 m/s)²

= (5.0-kg) (9×10^16m²/s²)

E =4.5×10^17 J