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:
Displacement = 70 m towards east
Explanation:
Displacement is the shortest distance between the two points.
Let us say that he starts at the point O and travels in a path ABC.
If we join the initial and final point of the path travelled by him, it will give the displacement of the man.
Distance from O to A = 40 m
Distance from A to B = 70 m
Distance from B to C = 40 m
Distance from O to A = Distance from B to C
We want the displacement which is distance between the points O and C
In rectangle opposite sides are equal. Hence Distance from O to C = Distance from A to B
Displacement = Distance from A to B
Hope it helps,
Please mark me as the brainliest.
Thank you
I think it is B as 168/20
Answer:
(a) 32.5 kgm/s
(b) 32.5 Ns
(c) 10.8 N
Explanation:
The change in momentum can be calculated from the definition of linear momentum:
Then, the change in momentum of the body is of 32.5 kgm/s (a).
Now, from the impulse-momentum theorem, we know that the change in momentum of a body 
is equal to the impulse 
exerted to it. So, the impulse produced by the force equals 32.5 kgm/s (or 32.5 Ns) (b).
Finally, since we know the value of the impulse and the interval of time, we can easily solve for the magnitude of the force:
It means that the magnitude of the force is of 10.8N (c).
