Answer:
ground state
Explanation:
Lets take
n=3 ,n=2 ,n=1 are the energy level.
Energy level n=1 is the ground energy level.
The energy from 3 to 1 = hν
The energy from 3 to 2 = hν₁
The energy from 2 to 1 = hν₂
We can say that
hν = hν₁ + hν₂
If the electron were de-excitation from the third level to ground level then the sum of emitted frequency will be equal to the frequency of a single electron.
Therefore the answer is ground state.
Answer:
The mass of the bullet is 15 g.
(b) is correct option.
Explanation:
Given that,
Momentum = 2.8 kg m/s
Speed = 187 m/s
We need to calculate the mass of the bullet
Using formula of momentum


Where, P = momentum
v = speed
Put the value into the formula



Hence, The mass of the bullet is 15 g.
In optics, you have to create a layer of coating that is approximately 1/4 of the light's wavelength. The working equation for this problem is:
d = λ₀/4n,
where
λ₀ is the wavelength of the incident light
n is the refractive index of the coating
Substituting the values,
d = (650 nm)/4(1.39)
<em>d = 116.9 nm</em>
<span>Correlations allow you to make inferences.</span>
D, when a moving car suddenly stops, your body is still moving forward until the seatbelt stops you.
When things move, there is always friction. It's what makes cars move in the first place. The inside of the car doesn't move, however the wheels on the car are moving at a rapid pace. When the car stops violently, everything inside the car is thrown. The seat belt acts as a safety precaution if an accident happens.
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