The bright lines visible in the emission spectrum of an element represent? A.
the energy released by electrons falling back to a ground state.

B. the colors seen when the element is viewed through a prism at room temperature.

C. the number of protons and neutrons present in the nucleus of the atom.

C. Other:

A2 kg ball travellng to the right with a speed of 4 m/s collidees with a 5 kg ball traveling to the left with a speed of 3 m/s. take right to be the positive direction. what is the total momentum of the two balls before they collide? what is the total momentum of the two balls after they collide?

If the temperature were raised very high, classically what would we expect the heat capacity per object to be for this one-dimensional system? give a numerical value. chigh t = __ j/k/object (one reason for the discrepancy is that the high-temperature limit assumes that the number of oscillators is large (n > > 1), which is not the case in this tiny system.)

How much energy must a refrigerator absorb from 225 g of water so that the temperature of the water will drop from 35°c to 5°c