A 140 W lightbulb emits 4% of its energy as electromagnetic radiation. What is the radiation pressure (in N/m2) on a perfectly absorbing sphere of radius 14 m that surrounds the bulb

Pr=7.57*10^{11}Pa

Explanation:

We can solve this problem by taking into account the expression

where I is the irradiance, c is the speed of light and A is the area.

We have that the power is 140W, but only 4% is electromagnetic energy, that is

56J is the electromagnetic energy.

The area of the bulb is

The radiation pressure is

hope this helps!!

not too sure thinking it will always be directed towards the centre of the earth. could be wrong not sure