Answer:
A)6.15 cm to the left of the lens
Explanation:
We can solve the problem by using the lens equation:

where
q is the distance of the image from the lens
f is the focal length
p is the distance of the object from the lens
In this problem, we have
(the focal length is negative for a diverging lens)
is the distance of the object from the lens
Solvign the equation for q, we find


And the sign (negative) means the image is on the left of the lens, because it is a virtual image, so the correct answer is
A)6.15 cm to the left of the lens
Answer
given,
wavelength of light in air = 700 nm
Wavelength of light in water = 530 nm
We know that speed of light changes when it moves from one medium to another.
And the frequency of the wavelength does not changes if the medium changes.
we also know that,
v = ν λ
From the above equation we can say that if frequency is constant so, with the change in velocity changes wavelength will also change.
Hence, wavelength is the property of the wave which determines color.
Answer:
r = 9.92 mm
Explanation:
Given that,
Mass of oil drop, 
It acquires 2 surplus electrons, q = +2e 
Potential difference, V = 620 V
Thie potential difference is applied between the pair of horizontal metal plates the drop is in equilibrium.
We need to find the distance between the plates.
At equilibrium,
mg = qE
Since, E = V/r (r is distance between plates)

So, the distance between the plates is 9.92 mm.
Answer:
(a) 
(b) The charge inside the shell is placed at the center of the sphere and negatively charged.
Explanation:
Gauss’ Law can be used to determine the system.

This is the net charge inside the sphere which causes the Electric field at the surface of the shell. Since the E-field is constant over the shell, then this charge is at the center and negatively charged because the E-field is radially inward.
The negative charge at the center attracts the same amount of positive charge at the surface of the shell.
Answer:
A constant value everywhere in the universe.
Explanation:
The speed of light in a vacuum is a constant value. It is not affected by change in frequency or wavelength of the light.
Mathematically the speed of light is given as:
c = λf
where λ = wavelength and f - frequency
The speed of light is the constant of proportionality between frequency and wavelength. In order words, wavelength and frequency are inversely proportional. As the wavelength increases, frequency decreases and vice versa.
While the change in wavelength and frequency of light affect the energy of the light, its speed is a constant value as long as the medium is a vacuum.
The speed of light is also not dependent on the manner with which the light wave is moving.