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:
Let us calculate gallon used in one hour .
It travels 70 miles in one hour
in 70 miles it uses 70 / 34 gallons of fuel
70 / 34 gallons = 70 / 34 x 3.7854 kg
= 7.8 kg
heat generated = 7.8 x 44 x 10⁶ J
= 343.2 x 10⁶ J
This is heat generated in one hour
heat generated in one second = 343.2 x 10⁶ / 60 x 60 J/s
= 95.33 x 10³ J /s
= 95.33 kW.
The time of a wave is 65 m/sec. if the wavelength of the wave is 0.8 meters. what is the speed of this wave?
answer- the speed is 52
Answer:
<h2>1) there is no work done on the system</h2><h2>2) A) Using a lever to lift 100 newtons up to 4 meters on to a shelf</h2><h2 /><h2>3) P = 140 W</h2><h2>4) D) In a closed system, a system that isolated from its surrounds, the total energy of the system is conserved</h2>
Explanation:
1) As we know that work done is the product of force and the displacement of the point of action where force is applied
So here we have
as there is no displacement in the direction where the force is applied
2)As we know that work is product of force and displacement
So we will have
So maximum work is done on
A) Using a lever to lift 100 newtons up to 4 meters on to a shelf
3)
As we know that power is rate of work done
so we have
4)
As per energy conservation we know that
D) In a closed system, a system that isolated from its surrounds, the total energy of the system is conserved
