1. The problem statement, all variables and given/known data Estimate the radiation pressure due to a 100-W bulb at a distance of 5.0 cm from the center of the bulb. Assume that light is complitely absorbed. Estimate the force exerted on your fingertip if you place it at this point. Assume area of the fingertip to be 1.5 cm2. 2. Relevant equations P = I/c I = Power/(4*pi*d2)?? 3. The attempt at a solution I don't know how to solve for intensity. I think it should have units of W/m^2 so I would guess it would be 100/(4*pi*.05*.05) = Power/(4*pi*d2), since 4*pi*d*d would be the area of a sphere of radius d but I doubt it is correct. For the second part it would just be the pressure I get in the first part times 0.00015 (1.5 cm2 in m2) for force. Thanks in advance!