an insulated thermos contains 130 cm cube of hot coffee at 80 degrees celsius. you put in a 12 gram ice cube at its melting point to cool the coffee. by how many degrees has your coffee cooled once the ice has melted and equilibrium is reached? treat the coffee as though it were water and...

It has been estimated that the Earth contains 109 metric tons of natural uranium that can be mined economically. Of this total, 0.7% is 235U that can be fissioned to produce energy. Assume 208 MeV per fission; 1 MeV = 1.6x10-13 J; 235 g of U has 6x1023 atoms. (15%) a. How many atoms of 235U...

A dentist uses a small mirror with a radius of 40 mm to locate a cavity in a patient's tooth. If the mirror is concave and is held 16 mm from the tooth, what is the magnification of the image?

(c) The atomic number of an element is 77. According to the Bohr model, what is the energy of a K x-ray photon?

The first atomic bomb released energy equivalent to 20 kilotons of TNT. If 1 ton of TNT releases 4x109 J, how much uranium was consumed through fission in the bomb? Assume 208 MeV per fission; 1 MeV = 1.6x10-13 J; 235 g of U has 6x1023 atoms. Hint: use the energy released and the energy per unit...

A pipe open only at one end has a fundamental frequency of 277 Hz. A second pipe, initially identical to the first pipe, is shortened by cutting off a portion of the open end. Now, when both pipes vibrate at their fundamental frequencies, a beat frequency of 11.1 Hz is heard. How many centimeters...

A layer of benzene 2.50 deep floats on water that is 6.50 deep. a) What is the apparent distance from the upper benzene surface to the bottom of the water layer when it is viewed at normal incidence?

A hollow sphere is rolling along a horizontal floor at 5.50 when it comes to a 28.0 incline. How far up the incline does it roll before reversing direction?

A convex lens of focal length 5 cm is used as a magnifying glass. At what distance from a tiny insect should you hold this lens to get a magnification of +2.7?

The maximum wavelength for which an electromagnetic wave can eject electrons from a platinum surface is 196 nm. When radiation with a wavelength of 142 nm shines on the surface, what is the maximum speed of the ejected electrons?