A hollow, conducting sphere with an outer radius of 0.257 m and an inner radius of 0.203m has a uniform surface charge density of +6.31×10−6C/m^2 . A charge of -0.870uC is now introduced into the cavity inside the sphere. Required:
a. What is the new charge density on the outside of the sphere?
b. Calculate the strength of the electric field just outside the sphere.
c. What is the electric flux through a spherical surface just inside the inner surface of the sphere?

True or false: the cycle of seasons on the earth is caused by the tilt of the earth on its axis toward and away from the sun.

Explain the difference between each pair of concepts. a. frequency and relative frequency b. percentage and relative frequency a. select the correct choice below. a. frequency is the total number of observations in a data set. relative frequency is the number of times a particular distinct value occurs. b. frequency is the number of times a particular distinct value occurs. relative frequency is the ratio of the frequency of a value to the total number of observations. c. frequency is the total number of observations in a data set. relative frequency is the ratio of the number of times a particular distinct value occurs to the frequency. d. frequency is the number of times a particular distinct value occurs. relative frequency is the ratio of the frequency of two different values.

Describe uniform velocity and variable velocity in short