A `2^(@)C` rise in temperature is observed in a conductor passing a current. When the current is tripled. The rise in temperature will be

Options

A. 18 C
B. 20 C
C. 22 C
D. 16 C

Answer

B

Explanation

On applying law of conservation of linear momentum
`vec(P)_(1) = vec(P)_(f) rArr 16 xx vec(0) = 4vec(v)_(4) + 12 xx 4 hat(i) rArr vec(v)_(4) = 12 (-hat(i))`
The `4 lg` block will move in a direction opposite to `12 kg` block with a speed of `12 m//s`. The corresponding kinetic energy of `4 kg` block
`= (1)/(2) xx 4 xx (12)^(2) = 288 J`