Answer:
Option A
Explanation:
This can be explained based on the conservation of energy.
The total mechanical energy of the system remain constant in the absence of any external force. Also, the total mechanical energy of the system is the sum of the potential energy and the kinetic energy associated with the system.
In case of two stones thrown from a cliff one vertically downwards the other vertically upwards, the overall gravitational potential energy remain same for the two stones as the displacement of the stones is same.
Therefore the kinetic energy and hence the speed of the two stones should also be same in order for the mechanical energy to remain conserved.
Answer:
perpendicular
Explanation:
Polaroids are the material that is used to polarize the ray of light. Polaroid consists of microcrystals of herapathite.
When unpolarized light is passed through the Polaroid then ray appears to be of half the intensity and vibration of the ray in the single plane so, the emerged light is known as polarized light
Polaroids are used in the glasses to protect the eye from unwanted rays.
When Light does not pass through a pair of Polaroids then the axis of Polaroids will be perpendicular to the axis of ray.
Answer:
evaporation to condensation to precipitation.
At surface,
v = kq/r
And potential energy of an electron is given by,
PE = -ev = -ekq/r
At escape velocity,
PE + KE = 0.
Therefore,
1/2mv^2 - ekq/r =0
1/2mv^2 = ekq/r
v = Sqrt [2ekq/mr], where v = escape velocity, e = 1.6*10^-19 C, k = 8.99*10^9 Nm^2/C^2, m = 9.11*10^-31 kg, r = 1.1*10^-2 m, q = 8*10^-9 C
Substituting;
v = Sqrt [(2*1.6*19^-19*8.99*10^9*8*10^-9)/(9.11*10^-31*1.1*10^-2)] = 47949357.23 m/s ≈ 4.795 *10^7 m/s
