A woman is walking, swinging her arms through a 30° angle every second. The length of each arm is 75 cm. Assuming that the arms move with constant speed during each swing, find the force that the blood vessel must exert on a 2-gram drop of blood from the end of the arm. A. 2 × 10−1 N
B. 2 × 10−2 N
C. 2 × 10−3 N
D. 2 N

Suppose a wire with a current is pushed upward by a magnetic field. how would the wire move if the direction of the current reversed? explain your answer.

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?

The nuclear potential that binds protons and neutrons in the nucleus of an atom is often approximated by a square well. imagine a proton conned in an innite square well of length 105 nm, a typical nuclear diameter. calculate the wavelength and energy associated with the photon that is emitted when the proton undergoes a transition from the rst excited state (n 2) to the ground state (n 1). in what region of the electromagnetic spectrum does this wavelength belong?