Step-by-step explanation:
It is given that the atom is hydrogen. And, its electron rotates in n = 5 orbit with angular speed
.
Radius of circular path =
m
Hence, first calculate the tangential speed as follows.
Tangential speed = radius × angular speed
=

As formula to calculate time period is as follows.
T =
sec
Also, frequency
=

So, for n = 5 and z = 1 the value of frequency is as follows.
frequency
=

=
=
Hz
As formula to calculate centripetal acceleration is as follows.

where, v = linear speed
r = radius
v =

=
=
Hence, the centripetal acceleration will be as follows.

=

=

Thus, we can conclude that the electron's centripetal acceleration is
.