Question

The radiation efficiency value is ______

(a) 0

(b) 1<η<∞

(c) 0≤η≤1

(d) ∞

Answer 1

Correct choice is (c) 0≤η≤1

Explanation: Radiation efficiency ηr=(frac{R_r}{R_r+R_l})

Rr+Rl>Rr So (frac{R_r}{R_r+R_l}) < 1 and If Rl=0 then ηr=1

Therefore, the value of efficiency lies in the range 0 to 1.