By what potential difference must a proton [m_0 = 1.67e-27 kg) be accelerated to have a wavelength lambda = 4.23e-12 m? by what potential difference must an electron [m_0 = 9.11e-31 kg), be accelerated to have a wavelength lambda = 4.23e-12 m?

A250-n box is at rest on a frictionless horizotal floor. then a person shoves the box with a non-zero force of magnitude p. which statement best describes the relationship betweeen p and the motion of the box after it was shoved? -the box will not move when p< 250n but otherwise will accelerate at a constant rate that is directly proportional to p - the box will begin moving at a speed that is directly proportional to p, then will gradually slow to a halt -the box will move with constant velocity at a speed that is directly proportional to p -box will accelerate across the floor at a constant rate that is directly proportional to p

The center of the milky way most likely contains a. empty space. b. a red giant star. c. a globular cluster. d. a supermassive black hole.

Give an example for each of the following situations: 1) negative acceleration, but positive velocity 2) positive acceleration and positive velocity 3) positive acceleration, but negative velocity 4) negative acceleration and negative velocity 5) positive velocity and no acceleration