Answer:
(a) Charge density σ=6.6375×10²nC/m²
(b) Total charge Q=1.47×10²nC
Explanation:
Given Data
A=47.0 cm =0.47 m
Electric field E=75.0 kN/C
To find
(a) Charge density σ
(b)Total Charge Q
Solution
For (a) charge density σ
From Gauss Law we know that
Φ=Q/ε₀.......eq(i)
Where
Φ is electric flux
Q is charge
ε₀ is permittivity of space
And from the definition of flux
Φ = EA
The flux is electric field passing perpendicularly through the surface
Put the this Φ in equation(i)
EA
=Q/ε₀
where Q(charge)=σA
EA=(σA)/ε₀
E=σ/ε₀
σ=ε₀E
σ=6.6375×10²nC/m²
For (b) total charge Q
Q=σA
Answer:
a) I = (
+ 
) L² , b) w = (\frac{27 M}{18 m} + 2)⁻¹ Lv₀
Explanation:
a) The moment of inertia is a scalar that represents the inertia in circular motion, therefore it is an additive quantity.
The moment of inertia of a rod held at one end is
I₁ = 1/3 M L²
The moment of inertia of the mass at y = L
I₂ = m y²
The total inertia method
I = I₁ + I₂
I = \frac{1}{3} M L² + m (\frac{2}{3} L)²
I = ( + ) L²
b) The conservation of angular momentum, where the system is formed by the masses and the bar, in such a way that all the forces during the collision are internal.
Initial instant. Before the crash
L₀ = I₂ w₀
angular and linear velocity are related
w₀ = y v₀
w₀ = 
L v₀
L₀ = I₂ y v₀
Final moment. After the crash
= I w
how angular momentum is conserved
L₀ = L_{f}
I₂ y v₀ = I w
substitute
m (
)² (\frac{2L}{3} v₀ = ( + ) L² w
m L³ v₀ = ( + ) L² w
m L v₀ = ( + ) w
L v₀ = 
w
w = (\frac{27 M}{18 m} + 2)⁻¹ Lv₀
As the dress is black it will absorb all colors with all different wavelengths
In short, Your Answer would be Option A
Hope this helps!
Answer:
800
cm²
Explanation:
Given parameters:
radius of the coin = 20cm
Unknown:
Surface area of the coin = ?
Solution:
A coin is made up of two faces;
Surface area = 2(πr²)
Insert the parameters and solve;
Surface area = 2(
)
Surface area = 800cm²
