Q = m.s.Δt
Δt = Q /m.s
Here, Q = 30,000 J
m = 390 g
s = 3.9 J/g C
Substitute their values,
= 30,000 / 390 *3.9
= 30,000 / 1521
= -20 C (approx.) [-ve sign 'cause temperature is decreasing ]
In short, Your Answer would be Option D
Hope this helps!
The answer is 1 the first one is the only one that makes sense
Answer:
gravitational potenetial energy =ℎ
Explanation:
none
Gamma rays are known to have the greatest frequency and the shortest wavelength. What we also know is that frequency and energy are directly proportional (they are the same), and that the wavelength is the opposite of them - if frequency/energy are high, the wavelength will be short, and vice versa.
Since X-rays are the opposite of gamma rays, then the correct answer is the third option <u />- <u>less energy and long wavelengths.</u>
Answer:
a. V = (a - b)d/2ε₀ b. 2ε₀A/d
Explanation:
a. The potential difference between the plates
Using Gauss' law, we first find the electric field between the plates
ε₀∫E.dA = Q where Q = charge enclosed, E = electric field
Now Q = [a +(-b)]A = (a - b)A where + a and -b are the surface charge densities of the plates and A is the area of the plates.
ε₀∫E.dA = Q
ε₀∫EdAcos0 + ε₀∫EdAcos0 = (a - b)A
ε₀E∫dA + ε₀E∫dA = (a -b)A
ε₀EA + ε₀EA = (a -b)A
2ε₀EA = (a -b)A
E = (a - b)/2ε₀
We now find the potential difference, V between the plates from
V = ∫E.dl
V =E∫dl
V = Ed where ∫dl = d the distance between the plates.
V = (a - b)d/2ε₀
b. The capacitance between them
Capacitance C = Q/V
= (a - b)A ÷ (a - b)d/2ε₀
= 2ε₀A/d