12 V is the f.e.m.

of the battery. The potential difference that is applied to the motor is actually the fem minus the voltage drop on the internal resistance r:

this is equal to the voltage drop on the resistance of the motor R:

so we can write:

and using

and

we can find the current I:
Earth's magnetic field is the force acting on the compass needle to cause it to point northeast.
Answer:
The electric flux is zero because charge is zero.
Explanation:
Given that,
Positive charge 
Negative charge 
We need to calculate the total charged
Using formula of charge

Put the value into the formula


We need to calculate the electric flux
Using formula of electric flux

Put the value into the formula

Hence, The electric flux is zero because charge is zero.
Answer:
Gases have three characteristic properties: 1. they are easy to compress, 2. they expand to fill their containers, and 3.they occupy far more space than the liquids or solids from which they form. Compressibility. An internal combustion engine provides a good example of the ease with which gases can be compressed.
Explanation: