Answer:
d sin tea = m λ
Explanation:
When we have a two-slit system, the optical path difference determines whether the intensity reaching an observation screen is maximum or zero.
To find this difference in optical path, we assume that the screen is much farther than the gap is, we draw a perpendicular from ray 1 to the second ray
OP = d sin θ
now to have constructive interference and see a bright line this leg must be an integer number of wavelengths, ose
d sin tea = m λ
where
d is the distance between the two slits
θ complexion the angle sea the point hold it between the two slits
λ the wavelength of the coherent light used
m an integer, which counts the number of lines of interference
Units in the SI system
d, lam in meters
θ degrees
m an integer
Answer:
First, as you may know, the light travels at a given velocity.
In vaccum, this velocity is c = 3x10^8 m/s.
And we know that:
distance = velocity*time
Now, if some object (like a star ) is really far away, the light that comes from that star may take years to reach the Earth.
This means that the images that the astronomers see today, actually happened years and years ago (So the night sky is like a picture of the "past" of the universe)
Also, for example, if an astronomer sees some particular thing, he can apply a model (a "simplification" of some phenomena that is used to simplify it an explain it) and with the model, the scientist can infer the information of the given thing some time before it was seen.
Answer:
Efficiency = 80%
Explanation:
Given the following data;
Work output = 240 N
Work Input = 300 N
To find the mechanical efficiency of a machine;
Substituting into the equation, we have;

Efficiency = 80%
Therefore, the mechanical efficiency of the machine is 80 percent.
Answer:
(a). The spring compressed is
.
(b). The acceleration is 1.5 g.
Explanation:
Given that,
Acceleration = a
mass = m
spring constant = k
(a). We need to calculate the spring compressed
Using balance equation

....(I)
The spring compressed is
.
(b). If the compression is 2.5 times larger than it is when the mass sits in a still elevator,
The compression is given by

Here, acceleration is zero
So, 
We need to calculate the acceleration
Put the value of x in equation (I)




Hence, (a). The spring compressed is
.
(b). The acceleration is 1.5 g.
Answer:
I=1.48 A
Explanation:
Given that
B=3.1 x 10⁻5 T
b= 4.2 cm
l= 9.5 cm
The relationship for magnetic field and current given as

Where

By putting the values


D=26.03 m⁻¹



I=1.48 A