Recent content by Dars

Homework Statement Modern electron microscopes used in biological research emit a beam of electrons with a velocity of 1.5x108 m/s a. What is the wavelength of an electron in the beam? b. The wavelength of the particle determines the resolution of the microscopy. Assume that you desire a...

Supercooled water freezes. Is this a spontaneous process?? Homework Statement "one mole of supercooled water at -10degC freezes reversibly to ice at -10degC at constant P of 1500atm. The system is at chemical equilibrium. Assume that ΔH_fusion is independent of temperature. Also assume that...

Homework Statement You want to heat 1 L of water by 10 ºC, and so you heat it with a mechanical egg beater that is powered by a 1 kg mass on a rope over a pulley. How far does the mass have to descend to supply enough work for heating the water? Homework Equations |work| = mg(x_f - x_0)...

What does infinitesimal change in V mean? Can someone please illustrate with simple example. Lecture notes say infinitesimal change in V = dV And large change in V is delta V.. I don't understand what it means though

simple question about "fixed volume" What exactly does "fixed volume" mean in thermodynamics, for a liquid? Does it mean that the container volume is fixed or that the volume of water is fixed, or that the volume of both the container and the water is fixed? This is confusing me because...

Homework Statement "You want to heat 1 L of water by 10 ºC so you heat it with a mechanical egg beater that is powered by a 1kg mass on a rope over a pulley. How far does the mass have to descend to supply enough work for heating the water? Homework Equations delta T = 10degC delta...

Homework Statement a telescope has a diameter of 8m. A double star 6000 light years away is viewed. what must be the min distance apart (in ly) of the two stars for their images to be distinguished if light of wavelength 500nm is used? Homework Equations theta = 1.22 (lamda/D) D =...

what is "counting rate"? Homework Statement Is "counting rate" the same as "rate of decay"? This problem asks about counting rate, but i can't see this term anywhere in my physics book.. Is it like an alternate term for "rate of decay" (also, counting rate isn't even on wikipedia)...

Homework Statement Two slit interference question: A screen is 2.2m from two slits. The distance from point P to point R (the central maximum to the 2nd dark band) is 1.6mm. This is what the pattern looks like (l) means light band... (d) means dark band ......P...R (d) (l) (d) (l) (d)...

Homework Statement I am 2 meters tall and I want to see my full image in a mirror. What is the minimum height the mirror should be? Homework Equations Why shouldn't min height be also 2m, because no magnification (plane mirror) ?? The Attempt at a Solution