7) PE= Fwh = (72 m) (966 N) = 69552 Joules 7
8) zero PE=mass*g*height
I hope it’s correct
Answer:
a)θ=71.89°
b)NO
Explanation:
Given that
For glass n= 1.38
We know that for air n'=1
The angle for total internal reflection θc given as
sin θc=n'/n
By putting the values
sin θc=n'/n
sin θc=1/1.38
θc=46.43°
n'sinθ = n sinθref
sinθref = cosθc
n'sinθ = n cosθc
1 x sinθ =1.38 x cos 46.43°
θ=71.89°
b)
NO
Answer:
U₁ = (ϵAV²)/6d
This means that the new energy of the capacitor is (1/3) of the initial energy before the increased separation.
Explanation:
The energy stored in a capacitor is given by (1/2) (CV²)
Energy in the capacitor initially
U = CV²/2
V = voltage across the plates of the capacitor
C = capacitance of the capacitor
But the capacitance of a capacitor depends on the geometry of the capacitor is given by
C = ϵA/d
ϵ = Absolute permissivity of the dielectric material
A = Cross sectional Area of the capacitor
d = separation between the capacitor
So,
U = CV²/2
Substituting for C
U = ϵAV²/2d
Now, for U₁, the new distance between plates, d₁ = 3d
U₁ = ϵAV²/2d₁
U₁ = ϵAV²/(2(3d))
U₁ = (ϵAV²)/6d
This means that the new energy of the capacitor is (1/3) of the initial energy before the increased separation.
