A diffraction grating has rulings of 890 lines/mm. When white light is incident normally on the grating, what is the longest wavelength that forms an intensity maximum in the fifth order

225nm

Explanation:

The Maxima of diffraction girating

dsin( θ)= m(λ)

Where θ)= angle between central axis and corresponding point

The wavelength is to corresponding sin( θ)

Then the maximum number of (λ) can be seen by setting sin( θ)= 1 then

d= m(λ)

At fifth order maximum m=1 then

d= 5(λ)

Where d= distance between the slit and with girating of 1/890rullig/mm

d= 1/890rullig/mm= 8.90×10^-6m

At maximum wavelength

d= 5(λ)

(λ)=5/d

= 8.90×10^-6m/5

=2.75*10^-7

= 275nm

Therefore, longest wavelength that forms an intensity maximum in the fifth order is 275nm

kepler used the data from tycho blahe (his mentor) to construct the laws of planetary motion.

the order for strong to weak forces such as

strong nuclear force → electromegnetic force → weak nuclear force → gravitational force

the fundamental forces are those forces that act between to objects or element to make interactions. there are four types of fundamental forces such as strong and weak nuclear forces (due to protons and electrons), electromagnetic force (due to the motion of electrons) and gravitational force (due to orbital movement of the planet). if these forces are arranged on the basis of their maximum strength then the order is

strong nuclear force → electromegnetic force → weak nuclear force → gravitational force