The force of radiation on the surface can be calculated using the formula F = IA, where F is the force, I is the intensity of radiation, and A is the area of the surface. In this case, we have an intensity of 62000 w/m2 and an area of 0.900 m2. So, plugging these values into the formula we get:
F = (62000 w/m2) x (0.900 m2)
F = 55800 N
Therefore, the force of radiation on the surface is 55800 N. This is because when light is reflected, it exerts a pressure on the surface that is equivalent to the force of the photons hitting it. This force can be significant, especially in situations where high-intensity light is being reflected, such as in laser applications or in solar energy collection. It is important to consider this force when designing systems that involve the reflection of light, in order to ensure that the materials used can withstand the pressure.