Question

What is the energy equivalent of 5.0kg of mass?

Answer 1

Ah hah ! Sounds to me like an " E = m c² " question.

c = 3 x 10⁶ m/s

c² = 9 x 10¹² m²/s²

E = (5 kg) x (9 x 10¹² m²/s²)

= 45 x 10¹² kg-m²/s²

= 4.5 x 10¹³ newton-m

= 4.5 x 10¹³ Joules .

That's the energy needed to

-- run a 1000-watt blow-dryer for roughly 1,427 years .
or
-- run a 400-horsepower truck, wide open, pedal to the metal,
for 4.78 years .

Answer 2

Answer : The energy equivalent if 5 kg of mass is
`4.5* 10^(17)\ J`

Explanation :

Given that,

Mass, m = 5 kg

From Einstein's mass - energy equivalence relation :

`E=mc^2`

E is energy

m is the mass of the object

c is the speed of light

`E=5\ kg* (3* 10^8\ m/s)^2`

`E=4.5* 10^(17)\ J`

Hence, this is the required solution.