An 8cm tall object is 15cm away from a lens and produces a real image that is twice the size of the object. A. Use the lens equation to calculate the focal length of the lens

B. If the same object were in the same position in front of a lens that had the same focal length as the one above, but was a diverging lens, how tall would the image be?

C. Now assume that the object is 6.0cm in front of the original converging lens. How tall will the resulting image be?

Two loudspeakers, 5.5 m apart and facing each other, play identical sounds of the same frequency. you stand halfway between them, where there is a maximum of sound intensity. moving from this point toward one of the speakers, you encounter a minimum of sound intensity when you have moved 0.33 m . assume the speed of sound is 340 m/s.part a) what is the frequency of the sound? part b) if the frequency is then increased while you remain 0.21 m from the center, what is the first frequency for which that location will be a maximum of sound intensity? express your answer to two significant figures and include the appropriate units.

Two identical stars with mass m orbit around their center of mass. each orbit is circular and has radius r, so that the two stars are always on opposite sides of the circle. (a) find the gravitational force of one star on the other. (b) find the orbital speed of each star and the period of the orbit. (c) how much energy would be required to separate the two stars to infinity?

Can you receive a shock severe enough to prevent you from releasing the wire from an ordinary outlet with dry hands? a. no b. yes explain