Two children, ferdinand and isabella, are playing with a waterhose on a sunny summer day. isabella is holding the hose in herhand 1.0 meters above the ground and is trying to spray ferdinand, who is standing 10.0 meters away. i know so far that she cannotspray ferdinand at the current position and with the curreentspeed of spray. i got stuck inthe following question:

to increase the range of the water, isabellaplaces her thumb on the hose hole and partially covers it. assuming that the flow remains steady, what fraction f of the cross-sectional area of the hose hole does shehave to cover to be able to spray her friend?

assume that the cross section of the hoseopening is circular with a radius of 1.5 centimeters.

Consider the particle-in-a-box problem in 1d. a particle with mass m is confined to move freely between two hard walls situated at x = 0 and x = l. the potential energy function is given as (a) describe the boundary conditions that must be satisfied by the wavefunctions ψ(x) (such as energy eigenfunctions). (b) solve the schr¨odinger’s equation and by using the boundary conditions of part (a) find all energy eigenfunctions, ψn(x), and the corresponding energies, en. (c) what are the allowed values of the quantum number n above? how did you decide on that? (d) what is the de broglie wavelength for the ground state? (e) sketch a plot of the lowest 3 levels’ wavefunctions (ψn(x) vs x). don’t forget to mark the positions of the walls on the graphs. (f) in a transition between the energy levels above, which transition produces the longest wavelength λ for the emitted photon? what is the corresponding wavele

Look at the electroscope, describe how you can cause the two leaves at the bottom to repel each other and stay that way

Answer fast! which lens can produce a virtual image and a real image? concave lens convex lens flat lens