Ball a is dropped from rest from a window. at the same instant, ball b is thrown downward; and ball c is thrown upward from the same window. which statement concerning the balls after their release is necessarily true if air resistance is neglected?
(a) at some instant after it is thrown, the acceleration of ball c is zero.
(b) all three balls strike the ground at the same time.
(c) all three balls have the same velocity at any instant.
(d) all three balls have the same acceleration at any instant.
(e) all three balls reach the ground with the same velocity.

Exercise 2. find the wavelength of a photon emitted when an electron jumps from the n = 3 energy level down to the n = 2 energy level. where is this photon in the electromagnetic spectrum?

Amoving company collects data about couches they move and displays the data in a table. the force along the ramp, the angle of the ramp, and the height the couch is raised to are shown. which statements correctly compare the work done to move the couches? check all that apply. the same amount of work is done for couches 1 and 3. the same amount of work is done for couches 2 and 3. the work for couch 1 is greater than the work for couch 2. the work for couch 2 is less than the work for couch 3. the work for couch 3 is greater than the work for couch 1. the work for couch 2 is greater than the work for couch 1.

Atruck driver is attempting to deliver some furniture. first, he travels 8 km east, and then he turns around and travels 3 km west. finally, he turns again and travels 13 km to his destination. what is the drivers distance