In the early 19th century christian doppler, an austrian physicist, proposed a theory regarding the properties of a moving source of sound. this is now known as doppler’s law or the doppler effect. what does this law state? a) the loudness of a moving source of sound is independent of the observer. b) the frequency of a moving source of sound is independent of the observer. c) the loudness of a moving source of sound is greater as it approaches an observer. d) the frequency of a moving source of sound is greater as it approaches an observer.

An object moves from position +34m to the position -15m in 15 seconds. what is the total displacement? what is the total velocity?

Photoelectrons with a maximum speed of 6.50 x 107 m/s are ejected from a surface in the presence of light with a frequency of 6.75 x 1014hz. if the mass of an electron is 9.10 x 10-31 kg, calculate in joules the maximum kinetic energy of a single electron. 3.84 x 10-15 j 1.92 x 10-15 j 5.92 x 10-23 j 3.07 x 10-16 j

Click the game tab at the bottom of the simulation and select level 1. (there is no seesaw balance for this part of the activity.) balance the first equation, and click check to see if you got it right. if you can’t balance it in the first try, you can try again. work through the five equations for level 1. click continue to go on to level 2, and later level 3. each level is more difficult than the one before. keep trying until all the equations are balanced. in one or two sentences, describe how you did in the balancing game. in a few more sentences, explain one strategy you learned for balancing more complex equations.