Answer:
25.06s
Explanation:
Remaining part of the question.
(A large stone sphere has a mass of 8200 kg and a radius of 90 cm and floats with nearly zero friction on a thin layer of pressurized water.)
Solution:
F = 60N
r = 90cm = 0.9m
M = 8200kg
Moment of inertia for a sphere (I) = ⅖mr²
I = ⅖ * m * r²
I = ⅖ * 8200 * (0.9)²
I = 0.4 * 8200 * 0.81
I = 2656.8 kgm²
Torque (T) = Iα
but T = Fr
Equating both equations,
Iα = Fr
α = Fr / I
α = (60 * 0.9) / 2656.8
α = 0.020rad/s²
The time it will take her to rotate the sphere,
Θ = w₀t + ½αt²
Angular displacement for one revolution is 2Π rads..
θ = 2π rads
2π = 0 + ½ * 0.02 * t²
(w₀ is equal to zero since sphere is at rest)
2π = ½ * 0.02 * t²
6.284 = 0.01 t²
t² =6.284 / 0.01
t² = 628.4
t = √(628.4)
t = 25.06s
Answer:
a) E = σ / 2 ε₀ =
Q / 2A ε₀, b) E = 2Q/A ε₀
Explanation:
For this exercise we can use Gauss's Law
Ф = E. dA =
/ ε₀
Let us define a Gaussian surface as a cylinder with the base parallel to the plane. In this case, the walls of the cylinder and the charged plate have 90 degrees whereby the scalar product is zero, the normal vector at the base of the cylinder and the plate has zero degrees whereby the product is reduced to the algebraic product
Φ = E dA = q_{int} / ε₀ (1)
As they indicate that the plate has an area A, we can use the concept of surface charge density
σ = Q / A
Q = σ A
The flow is to both sides of loaded plate
Φ = 2 E A
Let's replace in equation 1
2E A = σA / ε₀
E = σ / 2 ε₀ =
Q / 2A ε₀
This is in the field at point P.
b) Now we have two plates each with a load Q and 3Q respectively and they ask for the field between them
The electric field is a vector quantity
E = E₁ + E₂
In the gap between the plates the two fields point in the same direction whereby they add
σ₁ = Q / A
E₁ = σ₁ / 2 ε₀
For the plate 2
σ₂ = -3Q / A = -3 σ₁
E₂ = σ₂ / 2 ε₀
E₂ = -3 σ₁ / 2 ε₀
The total field is
E = σ₁ / 2 ε₀ + 3 σ₁ / 2 ε₀
E = σ₁ / 2 ε₀ (1+ 3)
E = 2 σ₁ / ε₀
E = 2Q/A ε₀
The force is gravitational because when something is falling is call gravitational
Answer:
206.62313 m/s
Explanation:
u = Muzzle speed
g = Acceleration due to gravity = 9.8 m/s²
= Angle at which the bullet is fired = 30°
h = Maximum height = 544 m
Maximum height is given by

The muzzle speed is 206.62313 m/s