Answer:
2.
Explanation:
The electric force between two point charges is given by Coulomb's law:
Here k is the Coulomb constant, 
and 
are the signed magnitudes of the charges and d the distance of separation between them. We need 
. So:
Answer:
Radiation
Explanation:
Conduction, convection and radiation are the three modes of heat transfer.
1. Conduction: When the one end is heated of any rod, the heat transfer to the other end by the vibrational motion of the molecules, it is called conduction.
The heat transfer in a solid is due to the conduction.
2. Convection: When the liquid or gas is heated, the molecules which is in contact to the heat, heated first and due to the decrease in density they moves up and the molecules on the upper side are higher in density so they moves down. These are called convection currents. The process continues till the entire liquid becomes heated. It generally takes place in liquids and gases.
3. Radiation: The process of heat transfer in which no molecules takes place is called radiation. The heat coming from sun is due to the radiation. It does not require any medium.
In the thermos bottle, as there is no air between the two layers, so the heat transfer is due to the radiation.
To identify which one is ionic compound, you would select the compound with the high melting point. Ionic compounds<span> have high </span>melting points<span> because the electrostatic interactions that hold the compounds together are very strong. Hope this answers the question.</span>
It will move in the direction you pushed it, but it will go at a certain velocity
If you look at the picture you will see how, but the answer is 0.5 Hz.
