You drop a stone down a well that is 9.5 m deep. how long is it before you hear the splash? the 9) speed of sound in air is 343 m/s and air resistance is negligible.

Unpolarized light of intensity i_0=750w/m^2 is incident upon two polarizers. after passing through both polarizers the intensity is i_2=280w/m^2. (a) what is the intensity of the light after it passes through the first polarizer in w/m^2? (b) write an equation for the angle between the polarizers in terms of the initial (i_0) and final (i_2) intensities. (c) find the angle between the polarizers in degrees.

Using the free-body diagram, calculate the net force acting on the sled. is the sled in a state of dynamic equilibrium?

What do the atoms of elements in the same group have in common? a. they have the same atomic numbers. b. they have the same average atomic masses. c. they have the same number of electron shells. d. they have the same number of electrons in their outermost shells.