# Question: Three of the fundamental constants of physics are the speed

Three of the fundamental constants of physics are the speed of light, c = 3.0 × 108 m/s, the universal gravitational constant, G = 6.7 × 10−11 m3 ⋅kg−1 ⋅s−2, and Planck's constant, h = 6.6 × 10−34 kg⋅ m2 ⋅ s −1.

(a) Find a combination of these three constants that has the dimensions of time. This time is called the Planck time and represents the age of the universe before which the laws of physics as presently understood cannot be applied.

(b) Using the formula for the Planck time derived in part (a), what is the time in seconds?

(a) Find a combination of these three constants that has the dimensions of time. This time is called the Planck time and represents the age of the universe before which the laws of physics as presently understood cannot be applied.

(b) Using the formula for the Planck time derived in part (a), what is the time in seconds?

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