A)<span>
dQ = ρ(r) * A * dr = ρ0(1 - r/R) (4πr²)dr = 4π * ρ0(r² -
r³/R) dr
which when integrated from 0 to r is
total charge = 4π * ρ0 (r³/3 + r^4/(4R))
and when r = R our total charge is
total charge = 4π*ρ0(R³/3 + R³/4) = 4π*ρ0*R³/12 = π*ρ0*R³ / 3
and after substituting ρ0 = 3Q / πR³ we have
total charge = Q ◄
B) E = kQ/d²
since the distribution is symmetric spherically
C) dE = k*dq/r² = k*4π*ρ0(r² - r³/R)dr / r² = k*4π*ρ0(1 -
r/R)dr
so
E(r) = k*4π*ρ0*(r - r²/(2R)) from zero to r is
and after substituting for ρ0 is
E(r) = k*4π*3Q(r - r²/(2R)) / πR³ = 12kQ(r/R³ - r²/(2R^4))
which could be expressed other ways.
D) dE/dr = 0 = 12kQ(1/R³ - r/R^4) means that
r = R for a min/max (and we know it's a max since r = 0 is a
min).
<span>E) E = 12kQ(R/R³ - R²/(2R^4)) = 12kQ / 2R² = 6kQ / R² </span></span>
Answer:
Explanation:
Since momentum is a vector, you, indeed, in <em>two dimension</em> collisions, you can decompose it in two components, the x-direction and the y-direction, such as you do with the force, which is a vector too.
The law of conservation of <em>momentum</em> states that the total momentum before and after the collision are conserved.
Let's assume a collision in one dimension: x-direction.
If object A is moving to the right, its momentum is to the right. If objcet B is at rest its momentum is zero. Then, if when object A collides with object B, the first stops, the second must move to the right with a momentum in the x-direction equal to the momentum that object A initially had.
You can apply the same reasoning if object A is moving in two dimensions, and, a similar one, if object B is not at rest: at the end the momentum in each direction before the collision has to be equal to the momentum in each direction after the collision.
Answer:
The heater power required is 2400 W. The power in the heater can be calculated as the product of the voltage line and the steady current:
Explanation:
Since this a position vs time graph, the velocity will be the slope of the line.
(5-3) / (3-0)
2/3 m/s
.6666 m/s
Answer:
Explanation: the graph is looking good just put a line to the dot