Aball dropped from a bridge strikes the water in 5s . calculate (a)the speed with which it strikes and (b) the height of the bridge

Modern physics a photon emitted from an excited hydrogen atom has an energy of 3.02 electron volts. which electron energy-level transition would produce this photon? a. n=1 to n=6 b. n=2 to n=6 c. n=6 to n=1 d. n=6 to n=2 i chose b but the correct answer is d can someone tell me why? and what's the difference?

Which graph represents motion with an object with positive velocity that is located at a position of 3 meters at a time of 0 seconds? a) a b) bb eliminate c) c d) d

An object resting on a table weighs 100 n. with what force is the object pushing on the table? with what force is the table pushing on the object? explain how you got your answer.