Planck's constant has the value
- A. 6.63 times 10 to the minus 34 J s
- B. 3.0 times 10 to the 8 J s
- C. 1.6 times 10 to the minus 19 J s
- D. 9.1 times 10 to the minus 31 J s
Explanation
The extreme smallness of Planck's constant is why quantisation is invisible in everyday life and only matters at atomic scale. The other values given are the speed of light, the electronic charge and the electron mass respectively, all of which appear alongside it in the same formulae. Knowing which constant is which prevents easy marks being dropped.