Answer:
Explanation:
The relationship between the current and the electric field inside a wire is given by the following equation:
where ρ is the resistivity, and J is the current density. The current density is the current per area:
The resistivity is the reciprocal of conductivity. Therefore,
Finally, the electric field can be found:
Answer: Option (c) is the correct answer.
Explanation:
When the child is tossed up into the air then she gains kinetic energy as the child has moved from its initial position.
It is given that mass is 20 kg, velocity is , and height is 2 m.
Calculate the kinetic energy of child as follows.
kinetic energy =
=
=
=
Also, when child falls off the ground then she will have gravitational potential energy.
Calculate gravitational potential energy of child as follows.
Potential energy = m × g × h
=
=