<span>` You can consider T to be in units of seconds/step. Frequency is the inverse of period, so
1/T = frequency and has units of steps per second. There will be 60 times as many steps in a minute.</span>
Answer:B
Explanation:
Given
speed of car 
mass of clump 
Radius of car tire 
Since the tire is rotating about axle so a centripetal force is acting constantly on each particle towards the center of tire.
Centripetal force is given by

where 



(inward)
Answer:
2.295 eV
Explanation:
maximum wavelength, λ = 542 nm = 542 x 10^-9 m
The work function of the metal is defined as the minimum amount of energy falling on the metal so that the photo electrons just ejects the surface of metal.

where, h is the Plank's constant and c be the speed of light
h = 6.634 x 10^-34 Js
c = 3 x 10^8 m/s


Wo = 2.295 eV
Thus, the work function of this metal is 2.295 eV.