**Answer:**

The spectral half-width is 11.1 nm.

**Explanation:**

we know that if f is the frequency and h is the planck constant, then the energy is given by:

E = h×f

but if c is the speed of light and λ is the wavelength then, f = c/λ.

E = [h×c]/λ

λ = [h×c]/E

then the change in λ is given by:

Δλ = [(h×c)/(E^2)]×ΔE

= [(h×c)/((h×c/λ)^2)]×ΔE

= [(λ^2)/(h×c)]×ΔE

but we also know that:

ΔE = 1.8×k×T , where k = 1.38×10^-23J/K and T = 20 + 273 = 293K

then the half-width is given by:

Δλ = [(λ^2)/(h×c)]×1.8×kT

= [((550×10^-9)^2)/((6.63×10^-34)×(3×10^8))]×1.8×(1.38×10^-23)×(293)

= 1.11×10^-8 m

≈ 11.1 nm

Therefore, the spectral half-width is 11.1 nm.

**Answer:**

0.12 K

**Explanation:**

height, h = 51 m

let the mass of water is m.

Specific heat of water, c = 4190 J/kg K

According to the transformation of energy

Potential energy of water = thermal energy of water

m x g x h = m x c x ΔT

Where, ΔT is the rise in temperature

g x h = c x ΔT

9.8 x 51 = 4190 x ΔT

ΔT = 0.12 K

Thus, the rise in temperature is 0.12 K.

**Explanation:**

"1 meter per second per second" means acceleration of an object. It is equal to the rate of change of velocity. Its SI unit is .

It is simply given by :

dv is change in velocity

dt is small interval of time

"1 meter per second per second" means that the velocity of an object can increase by 1 meter per second.

The theory is that a <span>cloud collapses to form a star and disk. </span>Planets<span> form from this disk. According to our current understanding, a star and its </span>planets<span> form out of a collapsing cloud of dust and gas within a larger cloud called a nebula. But the truth is that God shaped them and created them with his hands</span>

**Answer:**

Option C

The toe can become an earthflow.

**Explanation:**

During wet weather especially winter season when snow is melting, the downhill toe of a slump is likely to become earthflow. It's incorrect to say that the toe turns into rock avalanche neither can the toe collapse and be deposited as a talus at the base of the slope. Despite the melting ice making clay sticky, the toe can't stop due to continued mass wasting that occurs. Therefore, the right answer is option C, <u>**The toe can become an earthflow**</u>