Given that,
Central maximum = 1 cm
Distance from the window shade to the wall =4 m
We know that,
The visible range of the sun light is 400 nm to 700 nm.
(a). We need to calculate the average wavelength
Using formula of average wavelength
Put the value into the formula
(b). We need to calculate the diameter of the pinhole
Using formula for diameter
Put the value into the formula
Hence, (a). The average wavelength 550 nm.
(b). The diameter of the pinhole is 0.537 mm.
Statements A, B, and C are true.
Statement <em> D is false</em>.
Answer: the refraction of light by the atmosphere
Explanation: Refraction is the phenomenon in which there is a change in direction of light passing from one medium to another or from a gradual change in the medium.
Here in case of sunset, the sun rays passes through the varying density of atmosphere because of varying concentrations of dust particles.
Reflection is the phenomenon in which the light bounces back after falling on a surface.
Absorption is the phenomenon in which matter captures the electromagnetic radiations and thus the energy of photons is converted to internal energy of the system.
Answer:
7.1 Hz
Explanation:
In a generator, the maximum induced emf is given by
where
N is the number of turns in the coil
A is the area of the coil
B is the magnetic field strength
f is the frequency
In this problem, we have
N = 200
B = 0.030 T
So we can re-arrange the equation to find the frequency of the generator:
Answer:
A. When it is in a magnetic field, it becomes a temporary magnet.
Explanation:
An iron bolt is attracted to a magnet because when in a magnetic field, the iron becomes a temporary magnet.
This is because the iron aligns their electrons in the magnetic fields.
- This causes that attraction between the magnet and the iron.
- Metals like iron are said to be ferromagnetic
- Unpaired electrons in iron spin in such a way that they align with the magnetic fields of the magnet.
