Answer:
Q = ba⁴ * ε₀
Explanation:
From Gauss's Law, we know that
flux Φ = Q / ε₀
where ε₀ = 8.85e-12 C²/N·m²
and also,
Φ = EAcosθ
The field is directed along the x-axis, so that all of the flux passes through the side of the cube at x = a. This means that θ = 0º, and thus
Φ = EAcos0
Φ = EA
E = bx² meanwhile, we are interested in the point where x = a, so we substitute and then
E = ba²
Since A = a² for the cube face, we have
Q / ε₀ = E * A
Q / ε₀ = ba² * a²
so that
Q = ba⁴ * ε₀
Answer:
-2 m/s^2
Explanation:
Acceleration is equal to the slope of the graph. You just find the slope of that section. The rise is -20 and the run is 10, so you get -2.
We can solve the problem by using the law of conservation of energy.
Using the ground as reference point, the mechanical energy of the brick when it is at 5 m from the ground is just potential energy (because the brick is initially at rest, so it doesn't have kinetic energy):

when the brick is at h'=3 m from the ground, its mechanical energy is now sum of kinetic energy and potential energy:

where v is the velocity of the brick. Since E is conserved, it must be equal to the initial energy (98.1 J), so we can solve this equation to find v:
Answer:
0.087 m
Explanation:
Length of the rod, L = 1.5 m
Let the mass of the rod is m and d is the distance between the pivot point and the centre of mass.
time period, T = 3 s
the formula for the time period of the pendulum is given by
.... (1)
where, I is the moment of inertia of the rod about the pivot point and g is the acceleration due to gravity.
Moment of inertia of the rod about the centre of mass, Ic = mL²/12
By using the parallel axis theorem, the moment of inertia of the rod about the pivot is
I = Ic + md²

Substituting the values in equation (1)


12d² -26.84 d + 2.25 = 0


d = 2.15 m , 0.087 m
d cannot be more than L/2, so the value of d is 0.087 m.
Thus, the distance between the pivot and the centre of mass of the rod is 0.087 m.
The average speed would have to be 260 km/hr due to the driver originally going 30 km/hr too slow the first two laps