A point charge with charge q1 is held stationary at the origin. A second point charge with charge q2 moves from the point (x1, 0) to the point (x2, y2). Please use k for Coulomb's constant rather than writing it out as (1/4πϵ0).How much work W is done by the electrostatic force on the moving point charge?

Decreased sensitivity to an unchanging stimulus is known as

A47.2 g block of copper whose temperature is 480 k is placed in an insulating box with a 91.8 g block of lead whose temperature is 200 k. (a) what is the equilibrium temperature of the two-block system? (b) what is the change in the internal energy of the two-block system between the initial state and the equilibrium state? (c) what is the change in the entropy of the two-block system? the heat capacities of copper and lead are 386 j/kg·k and 128 j/kg·k, respectively.

You add 800 ml of water at 20c to 800 ml of water at 80c what is the most likely final temperature of the mixture ? a. 100c b. 60c c. 25 c d.50c