Answer:
where E = electric field intensity
Explanation:
As we know that plastic ball is suspended by a string which makes 30 degree angle with the vertical
So here force due to electrostatic force on the charged ball is in horizontal direction along the direction of electric field
while weight of the ball is vertically downwards
so here we have
since string makes 30 degree angle with the vertical so we will have
where E = electric field intensity
The correct answer is A.
The coefficient of absorption of material A is 30%. So, the material will absorb 30% energy of the incident wave falling on it. Thus, the reflected wave will carry the rest 70% energy.
The coefficient of absorption of material B is 47%. So, the material will absorb 47% energy of the incident wave falling on it. Thus, the reflected wave will carry the rest 53% energy.
The coefficient of absorption of material C is 62%. So, the material will absorb 62% energy of the incident wave falling on it. Thus, the reflected wave will carry the rest 28% energy.
Hence, material C would be the best, because the percentage of the energy in an incident wave that remains in a reflected wave from this material is the smallest.
Answer:
A. Repeating an experiment to verify results
Explanation:
A scientific theory may be defined as the theory of science that is a thought out explanation of the observations done in the nature or that happens in the natural world. They are constructed using several scientific methods by observing many facts and hypothesis.
According to the question, repeating of an experiment a number of times and verifying its result may help in improving a scientific theory as if we get the similar result for each experiments, then it confirms the basis of the hypothesis or the facts that are observe in the nature and conclude a scientific theory.
This question is incomplete.Here is complete one
Consider a telescope with a small circular aperture of diameter 2.0 centimeters.
If two point sources of light are being imaged by this telescope, what is the maximum wavelength (lambda) at which the two can be resolved if their angular separation is 3.0x10^-5 radians? Express your answer in nanometers
Answer:
λ =492nm
Explanation:
Given Data
diameter=2.0 cm
angular separation=3.0x10^-5 radians
λ=?
Solution
sin(theta) = 1.22 x λ /D
λ=(0.02×sin(3.0×10⁻⁵))/1.22
λ=492nm
