What would be the potential difference on a test charge if it was 5nm away from 4nC charge? explain.

If element x has 99 protons how many electrons does it have

The path of a satellite orbiting the earth causes it to pass directly over two tracking stations a and b, which are 51 miles apart. when the satellite is on one side of the two stations, the angles of elevation at a and b are measured to be 87 degrees and 84 degrees, respectively. (a) how far is the satellite from station a? (b) how high is the satellite above the ground?

Stephanie lives in california, and her cousin thomas lives in france. which coordinate system would be most useful if the two wanted to observe the same meteor shower and discuss their observations over online chat as they're making them? a. horizontal b. equatorial c. azimuth-altitude d. celestial or azimuth-altitude