An electron is constrained to the central axis of a ring of charge 1 coulomb and of radius 1 meter. The electrostatic force exerted on the electron can cause the electron to oscillate through the center of the ring. Find the frequency of small oscillation of the electron in Hertz

A4.0-cm tall light bulb is placed a distance of 32.0 cm from a concave mirror having a focal length of 16.0 cm. determine the image distance

Asteel tube (k=50 w/mk) of inner and outer diameter di = 20mm and do=26mm, respectively, is used to transfer heat from hot gases flowing over the tube (h-hot = 200w/m2k) to cold water flowing through the tube (h-cold = 8000 w/m2k). what is the cold-side overall heat transfer coefficient uc? to enhance heat transfer 16 straight fins of rectangular profile are installed longitudinally along the outer surface of the tube. the fins are equally spaced around the circumference of the tube, each having a thickness of 2mm and a length of 15mm. what is the corresponding overall heat transfer coefficient uc? *solve for uc in both cases*

Adielectric-filled parallel-plate capacitor has plate area a = 30.0 cm2 , plate separation d = 9.00 mm and dielectric constant k = 3.00. the capacitor is connected to a battery that creates a constant voltage v = 15.0 v . throughout the problem, use ϵ0 = 8.85x10-12 c2/n. m2 . find the energy u1 of the dielectric-filled capacitor.