38. (II) Show that the following combination of the three fundamental constants of nature that we used in Example 1-10 (that is G, c, and h ) forms a quantity with the dimensions of time:

 38. (II) Show that the following combination of the three fundamental constants of nature that we used in Example 1-10 (that is G, c, and h ) forms a quantity with the dimensions of time:

$$

t_{ P }=\sqrt{\frac{G h}{c^{5}}}

$$

This quantity, $t_{ P },$ is called the Planck time and is thought to be the earliest time, after the creation of the Universe, at which the currently known laws of physics can be applied.