Answer: the expanding universe
Explanation:
Hope that helps!
Answer:
D.
Explanation:
Red light has wavelengths around 620 to 750 nm.
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.
Answer:
72km/hr
Explanation:
Speed in Km is usually represented in hours. so if the car is in constant velocity, and if the car travels 36km in 30 min then it travels 72km in 1 hour.
so the speed of the car is 72km/hr