Answer:
a) 7.947 radians
b) 
Explanation:
y = Distance from central bright fringe = 2.5 mm
λ = Wavelength = 600 nm
L = Distance between screen and source = 2.8 m
d = Slit distance = 0.85 mm


a) Phase difference

∴ Phase difference between the two interfering waves on a screen at a point 2.50 mm from the central bright fringe is 7.947 radians
b) 
∴ Ratio of the intensity at this point to the intensity at the center of a bright fringe 
metals are conductors, meaning that heat travels through it better than insulators such as plastic (commonly used for pan handles)
Therefore, to avoid the heat burning hands, most pans don't have metal handles.
The answer is B, Law of Kinetic Energy
Answer:
Time, t = 80 seconds
Explanation:
Given that,
The frequency of the oscillating mass, f = 1.25 Hz
Number of oscillations, n = 100
We need to find the time in which it makes 100 oscillations. We know that the frequency of an object is number of oscillations per unit time. It is given by :



t = 80 seconds
So, it will make 100 oscillations in 80 seconds. Hence, this is the required solution.
Answer: 539.4 N
Explanation:
Let's begin by explaining that Coulomb's Law establishes the following:
"The electrostatic force
between two point charges
and
is proportional to the product of the charges and inversely proportional to the square of the distance
that separates them, and has the direction of the line that joins them"
What is written above is expressed mathematically as follows:
(1)
Where:
is the electrostatic force
is the Coulomb's constant
and
are the electric charges
is the separation distance between the charges
Then:
(2)
Isolating
and
:
(3)
Now, if we keep the same charges but we decrease the distance to
, (1) is rewritten as:
(4)
Then, the new electrostatic force will be:
(5) As we can see, the electrostatic force is increased when we decrease the distance between the charges.