A radiation of 200 W is incident on a surface which is 60% reflecting and 40% absorbing. The total force on the surface is

1.07 × 10−6N 1.3 × 10−6N 1.07 × 10−7N 1.03 × 10−7N

1.07 × 10−6N

$F_{total} + F_{ref} + F_{abs}$ $=\frac{1.2P}{c}+\frac{0.4P}{c}=\frac{1.6P}{c}$ $=\frac{1.6×200}{3×10^8}=1.07 × 10^{-6} N$