White light consisting of wavelengths 380nm < 1< 750 nm is incident on a lead surface. For which one of the following ranges of wavelength will photoelectrons be emitted from the
elad surface that has a work funcation W. = 6.63 x 10-29 J?

Which of the following changes will result in a stronger electromagnet? a. using fewer coils of wire b. using a higher voltage c. using a shorter nail d. using a longer wire

In the first law of thermodynamics, triangle e=q-w, what does q stand for

Awater slide of length l has a vertical drop of h. abby's mass is m. an average friction force of magnitude f opposes her motion. she starts down the slide at initial speed vi. use work-energy ideas to develop an expression for her speed at the bottom of the slide. then evaluate your result using unit analysis and limiting case analysis. express your answer in terms of the variables h, m, l, vi, f and appropriate constants. vf v f