Answer:
3.6 × 10⁵ N/C = 360 kN/C
Explanation:
Let R = 2.0 cm be the radius of the sphere and q = -8.0 nC be the charge in it. Let q₁ be the charge at radius r = 1.0 cm. Since the charge is uniformly distributed, the volume charge density is constant. So, q/4πR³ = q₁/4πr³
q₁ = q(r/R)³. The electric field due to q₁ at r is E₁ = kq₁/r² = kq(r/R)³/r² = kqr/R³
The electric field due to the point charge q₂ = 5.0 nC is E₂ = kq₂/r².
So, the magnitude of the total electric field at r = 1.0 cm is
E = E₁ + E₂ = kqr/R³ + kq₂/r² = k(qr/R³ + q₂/r²)
E = 9 × 10⁹(-8 × 10⁻⁹ C × 1 × 10⁻² m/(2 × 10⁻² m)³ + 5 × 10⁻⁹ C/(1 × 10⁻² m)²)
E = 9 × 10⁹(-1 × 10⁻⁵ + 5 × 10⁻⁵)
E = 9 × 10⁹(4 × 10⁻⁵)
E = 36 × 10⁴ N/C = 3.6 × 10⁵ N/C = 360 kN/C
Energy = 1/2mv^2
Mass = 130kg
Speed = 5m/s
1/2 x 130 x 25
= 1625J
More massive attacking objects speed slows down and it transfer its some kinetic energy to less massive target objects whereas less massive target objects starts its motion
Knowing the force and distance allows you to calculate the work done.
Then, if you know the TIME, you can calculate the power.