(a) calculate little g on the surface of the sun. (b) now, say 90 kg b is in an elevator on the sun with the international scale and the elevator is accelerating down at 25 ge , where ge = 10 m/s 2 . what does the scale display? use g = 6.67 ⨉ 10 -11 n m2 /kg 2 , sun mass: 2 ⨉ 10 30 kg, sun radius: 700,000 km.

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?

Aparticle's position is given by x = 3.00 - 9.00t + 3t2, in which x is in meters and t is in seconds. (a) what is its velocity at t = 1 s? (b) is it moving in the positive or negative direction of x just then? (c) what is its speed just then? (d) is the speed increasing or decreasing just then? (try answering the next two questions without further calculation.) (e) is there ever an instant when the velocity is zero? if so, give the time t; if not, answer "0". (f) is there a time after t = 3 s when the particle is moving in the negative direction of x? if so, give the time t; if not, answer "0".

The electric field inside a battery generates an electric potential difference of 12v. the plates are seperated by a distance of 0.25m. what strength of the electric field?