Answer: the answer would be four thousand
Explanation: hope this helps
Scientists have been observing Earth for a long time. They use NASA satellites and other instruments to collect many types of information about Earth's land, atmosphere, ocean and ice. This information tells us that Earth's climate is getting warmer.
Extra:
Extra greenhouse gases in our atmosphere are the main reason that Earth is getting warmer. Greenhouse gases, such as carbon dioxide (CO2) and methane, trap the Sun's heat in Earth's atmosphere.
It's normal for there to be some greenhouse gases in our atmosphere. They help keep Earth warm enough to live on. But too many greenhouse gases can cause too much warming.
The burning of fossil fuels like coal and oil increase the amount of CO2 in our air. This happens because the burning process combines carbon with oxygen in the air to make CO2.
It's important that we monitor CO2 levels, because too much CO2 can cause too much warming on Earth. Several NASA missions have instruments that study CO2 in the atmosphere.
Answer:
a) -2.516 × 10⁻⁴ V
b) -1.33 × 10⁻³ V
Explanation:
The electric field inside the sphere can be expressed as:

The potential at a distance can be represented as:
V(r) - V(0) = 
V(r) - V(0) =
₀
V(r) =
₀
Given that:
q = +3.83 fc = 3.83 × 10⁻¹⁵ C
r = 0.56 cm
= 0.56 × 10⁻² m
R = 1.29 cm
= 1.29 × 10⁻² m
E₀ = 8.85 × 10⁻¹² F/m
Substituting our values; we have:

= -2.15 × 10⁻⁴ V
The difference between the radial distance and center can be expressed as:
V(r) - V(0) = 
V(r) - V(0) = ![[\frac{qr^2}{8 \pi E_0R^3 }]^R](https://tex.z-dn.net/?f=%5B%5Cfrac%7Bqr%5E2%7D%7B8%20%5Cpi%20E_0R%5E3%20%7D%5D%5ER)
V(r) = 
V(r) = 
V(r) 
V(r) = -0.00133
V(r) = - 1.33 × 10⁻³ V
Answer:
Explanation:
Let the angle between the first polariser and the second polariser axis is θ.
By using of law of Malus
(a)
Let the intensity of light coming out from the first polariser is I'
.... (1)
Now the angle between the transmission axis of the second and the third polariser is 90 - θ. Let the intensity of light coming out from the third polariser is I''.
By the law of Malus

So,



(b)
Now differentiate with respect to θ.


Electromagnets have certain advantages over permanent magnets. One of the major advantage is, the amount of electric current can easily be controlled, in turn, magnetic field can be controlled. Out of all the options, option D would be the best answer.
In short, Your Answer would be option D) Electromagnets can easily be turned on and off.
Hope this helps!