The wavelength and velocity of a set of plane waves travelling in a medium are 60cm and 320cm/s, respectively. It meets a plane refracting surface at an angle of incidence of 60^0. It's velocity after refraction is 280cm/s. Calculate the wavelength of the waves in the second medium and also the angle of refraction.

If you mix chlorine lithium and nickel together which two elements would be the most reactive

Four point charges each having charge q are located at the corners of a square having sides of length a. find symbolic expressions for the following. (a) the total electric potential at the center of the square due to the four charges (use any variable or symbol stated above along with the following as necessary: ke.) vtotal= (b) the work required to bring a fifth charge p from infinity to the center of the square (use any variable or symbol stated above along with the following as necessary: w=

An element becomes a positively charged ion when itloses protons.loses electrons.gains electrons.gains neutrons.