3. A particle of charge +7.5 µC is released from rest at the point x = 60 cm on an x-axis. The particle begins to move due to the presence of a charge that remains fixed at the origin. What is the kinetic energy of the particle at the instant it has moved 40 cm if a) = +20 µC and b) = −20 µC?

Apackage of supplies is dropped from a plane, and one second later a second package is dropped. neglecting air resistance, the relative velocity of the 1st package viewed from the second will 56) a) increase. b) be constant. c) be zero. d) depend upon their weight. e) decrease

Ablock of mass 1.5 kg slides down an inclined plane that has an angle of 15. if the inclined plane has no friction and the block starts at a height of 3 m, how much kinetic energy does the block have when it reaches the bottom? acceleration due to gravity is g = 9.8 m/s2. a. 6.8 j b. 50.9 j c. 0 j d. 44.1 j

What is the energy of a photon of ultraviolet radiation with a frequency of 4.4 × 1015 hz? planck’s constant is 6.63 × 10–34