Charge q1q1 is distance rr from a positive point charge qq. Charge q2=q1/3q2=q1/3 is distance 2r2r from qq. What is the ratio u1/u2u1/u2 of their potential energies due to their interactions with qq?.

Which of the following represents an upside-down image?

Ablock of mass m = 2.5 kg is attached to a spring with spring constant k = 790 n/m. it is initially at rest on an inclined plane that is at an angle of 28 degrees with respect to the horizontal, and the coefficient of kinetic friction between the block and the plane is k = 0.14. in the initial position, where the spring is compressed by a distance of a = 0.18 m, the mass is at its lowest position and the spring is compressed the maximum amount. take the initial gravitational energy of the block as zero. b) if the spring pushes the block up the incline, what distance, l, in meters will the block travel before coming to rest? the spring remains attached to both the block and the fixed wall throughout its motion.

You've already seen the value of 9.8 in this lesson. what's this value called? what quantity does it represent?