How do you calculate the work function of a metal without being given the frequency for the photoelectric effect? i am only given the speed the electrons are ejected from the metal, and the energy from the light that struck the electrons. i have used E = hf to find the frequency but I don’t know how to find the kinetic energy to plug into the photoelectric equation KE = hf - (work function)

A23 kg log of wood begins from rest, 300 m up a sluice (a water track used to transport logs, think of it as an inclined plane with negligible friction) inclined at 20° to the horizontal. after it reaches the flat waterway at the bottom it collides elastically with a 100 kg block of wood initially at rest near the base of the incline. (a) how long does it take the 23 kg log to travel down the incline? (b) what is the speed of the 23 kg log at the bottom of the incline? (c) what are the velocities of both blocks of wood after the collision? (d) what is the total kinetic energy before the collision? (e) what is the kinetic energy of the 23 kg log after the collision? (f) what is the kinetic energy of the 100 kg block of wood after the collision? (g) what is the total kinetic energy after the collision? (h) compare the total initial and total final kinetic energies. is this consistent with what you would expect for elastic collisions? explain!

Against his financial advisor's advice, frank has decided to invest his money in some risky stocks because he once made quite a bit of money in the stock market. his decision illustrates a. the representativeness heuristic b. overconfidence c. the availability heuristic d. confirmation bias select the best answer from the choices provided

Ahot-air balloon is 11.0 m above the ground and rising at a speed of 7.00 m/s. a ball is thrown horizontally from the balloon basket at a speed of 9.00 m/s. ignore friction and air resistance and find the speed of the ball when it strikes the ground.