We would like to find a relation between mass of black hole and the area of its event horizon A. This area depends on the mass of black hole, speed of light and universal gravitational constant. We write it as `A = G ^( alpha ) c ^( beta ) m ^( gamma).` Then the value of `|alpha + beta - gamma|` is

Answer

4

Explanation

`L ^(2) = [ M ^(-1) L ^(3) T ^(-2) ] ^( alpha ) [LT ^(-1)] ^(beta) [M] ^( gamma)`
`-alpha + gamma = 0`
`- 2 alpha - beta = 0`
` 3 alpha + beta =2`
` implies alpha =2, beta =- 4, gamma =2`