A point charge q1 is at the center of a sphere of radius 20 cm. Another point charge q2 = 10 nC is located at a distance r = 10 cm from the center of the sphere. If the net flux through the surface of the sphere is 800 N. m2/C, find q1.

Astudent in a science lab is investigating heat transfer and thermal energy conservation as she mixes hot and cold water. she first measures out her desired amount of cold water into a styrofoam cup. she then measures out hot water from the faucet or from a pot hot water on her stove. after she measures the temperature of the hot and cold waters, she pours the hot water into the cold water. she monitors the temperature of the mixed waters and records the final temperature. she uses a standard thermometer to record the temperatures. she does three trials, which are shown below: