Two identical charged pith balls are brought together to touch each other. They are then allowed to move freely. The charge on pith ball A is –30 nC and on pith ball B is – 5 nC.
What is the charge on each after they separate?

Which type of electromagnetic waves are dangerous enough to be used to kill cancerous cells? (a)gamma rays (b)visible light (c)infrared light (d)microwaves

Calculate the mass of an object that has a momentum of 100kg x m/sec and velocity of 4 m/sec

Unpolarized light of intensity i_0=750w/m^2 is incident upon two polarizers. after passing through both polarizers the intensity is i_2=280w/m^2. (a) what is the intensity of the light after it passes through the first polarizer in w/m^2? (b) write an equation for the angle between the polarizers in terms of the initial (i_0) and final (i_2) intensities. (c) find the angle between the polarizers in degrees.