DIRECTLY PROPORTIONAL AND INDIRECTLY PROPORTIONAL

Consider the following statements : 1. If x is directly proportional to z and y is directly proportional to z, then (x^(2) - y^(2)) is directly proportional to z^2 . 2. If x is inversely proportional to z and y is inversely proportional to z, then (xy) is inversely proportional to z^2 . Which of the above statements is/are correct?

Select the correct statements for hydrogen like atoms or ions. (A) Radius of an orbit is inversely proportional to Z (B) Radius of an orbit is directly proportional Z^2 (C) Total energy of the electron in an orbit is inversely proportional to Z (D) Magnitude of total energy of the electron in an orbit is directly proportional to Z^(2)

The time period of a pendulum is directly proportional to ______

The rate of chemical reaction is directly proportional to

The rate of chemical change is directly proportional to …………… .