A +1.4 nC charge exerts a repulsive force of 20.0 mN on a second charge which is located a distance of 2.2 m away from it. What is the magnitude and sign of the second charge?

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=

A200 g lead frying pan gains 2000 joules of heat. what is the change in temperature

You need to fill a basketball with air to play with it. you know that your pump expels air at a velocity of 6 cm/s. you know that the volume flow rate of air being pumped into the basketball is 103 cm^3/s. what is the diameter of your needle?