When a particular solar cell is exposed to a 6.6 x 1014 Hz light source, it can charge batteries up to 690 mv. A. What is the work function of the solar cell? B. What's the smallest frequency of light that can be used to power the solar cell?

Edrops Epuddle If a puddle of liquid on a table is converted into a collection of 28 drops, by what factor c = does the surface energy change? Round your answer to two decimals. Assume that the original pool was flat with a depth of 1.2 mm and that the drops are spherical caps (you can Google this), each with a height of 4.0 mm and a radius of 10.5 mm. The side area of the puddle can be neglected. c =

Please show all work and answer all parts

Choose the letter of the correct answer. Write the letter in CAPITAL LETTERS. [[ for questions 2 and 4 the image is attached ]] 1. In which one of the following situations is zero net work done?(a) A ball rolls down an inclined plane.(b) A physics student stretches a spring.(c) A projectile falls toward the surface of Earth.(d) A box is pulled across a rough floor at constant velocity.(e) A child pulls a wagon across a rough surface causing it to accelerate.   2. A concrete block is pulled 7.0 m across a frictionless surface by means of a rope. The tension in the rope is 40 N; and thenet work done on the block is 247 J. What angle does the rope make with the horizontal? (a) 28°                    (b) 41°                         (c) 47°                     (d) 62°                  (e) 88°   3. Mike is cutting the grass using a human-powered lawn mower. He pushes the mower with a force of45 N directed at an angle of 41° below the horizontal direction. Calculate the work that Mike does…