8 not counting Pluto 9 if counting Pluto, Pluto is technically not a planet anymore so best dentures 8.
Answer:
A. Zero
Explanation:
Given data,
The charge of the test charge, q = 1 C
The distance moved against the field of intensity, r = 30 cm
= 0.3 m
The electric field, E = 50 N/C
The formula for energy stored in the charge is,
V = k q/r
Where,
= 9 x 10⁹ Nm²C⁻²
The charge is moved from the potential V₁ to V₂ at 30 cm
Substituting the given values in the above equation
V₁ = 9 x 10⁹ x 30 / 0.3
= 1.5 x 10¹² J
And,
V₂ = 1.5 x 10¹² J
The energy stored in it is,
W = V₂ - V₁
= 0
Hence, the energy stored in the charge is, W = 0
Answer:
Emitted power will be equal to
Explanation:
It is given factory whistle can be heard up to a distance of R=2.5 km = 2500 m
Threshold of human hearing
We have to find the emitted power
Emitted power is equal to
So emitted power will be equal to
<span>The answer to this question would probably be "</span><span>D. The same background radiation was observed coming from all directions of space."
The background radiation here is referring to the Cosmic Microwave Background Radiation, one of the observational evidences of the Big Bang Theory which was discovered by Penzias and Wilson as they were doing some observations with a microwave receiver. </span>
For any object thrown upwards where only the force of gravity is acting upon it, uses the following formula for the maximum height attained.
H= v²/2g, where g = 9.81 m/s²
There are two information of velocities are given. However, we use the 20 m/s information because this is the launch velocity. Hence, the solution is as follows:
H = (20 m/s)²/2(9.81 m/s²)
<em>H = 20.4 m</em>