Question

The time dependence of a physical quantity P is given by `P=P_(0) exp (-alpha t^(2))`, where `alpha` is a constant and t is time. The constant `alpha`
A. diemensionless
B. has dimensions `T^(-2)`
C. has dimensions of P
D. has dimensions `T^(2)`

Answer 1

`P-P_(0)e^(-alphat^(2)`
`alphat^(2)` must be dimensionaless
Thus dimensions of `alpha=(1)/(t^(2))=T^(2)`