Complete Question:
Two small objects each with a net charge of Q (where Q is a positive number) exert a force of magnitude "F" on each other. We
replace one of the objects with another whose net charge is 4Q. The original magnitude of the force on the Q charge was "F"; what is the magnitude of the force on the Q charge now?
Answer:
4 F₀
Explanation:
Assuming that we can treat to both objects as point charges, we can find the force "F" that one charge exerts upon the other applying Coulomb´s law, as follows:
F₀ = K*Q₀² / r₁₂²
If we replace one of the charges by one with a 4Q₀ charge, the new value of F will be as follows:
F₁ = K*Q₀*4Q₀ / r₁₂² =( K*Q₀² / r₁₂²)* 4 = 4* F₀
This value is reasonable, as the electrostatic force is a linear - type one, so it is possible to use the superposition principle (we can get the force exerted by one charge on another without considering the ones due to another charges)
Answer:
Anita 's power rating during this portion of the climb is 1568 Watts.
Explanation:
Given that,
Mass of the body, m = 800 kg
Height, h = 20 m
Time, t = 100 s
We need to find the Anita 's power rating during this portion of the climb. Power rating of an object is given by the work done per unit time. It is given by :



P = 1568 Watts
So, Anita 's power rating during this portion of the climb is 1568 Watts. Hence, this is the required solution.
The electric field depends not on the magnetic field, but change in magnetic field. if the magnetic field is constant. electric field will be zero.
Explanation:
When a bullet is fired from a rifle, the actual firing makes a distinctive sound, but people at a distance may hear a second because the bullet creates a shock wave , a little sonic boom( speed of this sonic boom is greater than the speed of sound). It is this sound only that is heard by the people at a distance from the gun.