Answer:
λ = 0.03 s⁻¹
Explanation:
The formula for decay constant can be used as follows:
where,
= ratio of remaining nuclei to the initial value of nuclei = = 0.167
t = time = 60 s
λ = decay constant = ?
Therefore,
<u>λ = 0.03 s⁻¹</u>
Answer:
All of the following are true EXCEPT, the angle of refraction is 30 degrees
Explanation:
It is given that,
The index of refraction of the water is 1.33 and the angle of incidence is 30 degrees. We know that when a ray of white light moves through the air and strikes the surface of water in a beaker, refraction occurs. Let r is the angle of refraction. It can be calculated using Snell's law as :
So, the angle of refraction is 22.08 degrees.
According to the law of reflection, the angle of incidence is equal to the angle of reflection. Since, it is incident at an angle of 30 degrees, so the angle of reflection will be 30 degrees. Also, total internal reflection will result, depending on the critical angle.
So, the wrong statement is the angle of refraction is 30 degrees. It is equal to 22.08 degrees.
Answer:
The correct option is (b) i.e. 0.03 m.
Explanation:
We have,
Speed of a wave is 0.09 m/s and the frequency of a wave is 3 Hz.
It is required to find the wavelength of a wave.
The speed of a wave in terms of wavelength and frequency is given by :
So, the wavelength of a wave is 0.03 m.
Because any other radiation can be harmful<span />