Answer:
The negative electrode of a battery has an excess of positive charge
Explanation:
This is because in every battery, there is a negative electrode ( cathode ) and only positive charge is deposited on it.
For other statements:
Batteries donot store electric charge but they store chemical energy
Some batteries donot use metals for the flow of electrons, but some use hydrogen gas at a pressure of 1 atmosphere.
The answer is B because oil = blockage of air and it pressures the water to be density of 0.90
Speed of any freely falling object is always same. Provided, both are left to fall from the same height. If you perform this experiment in a perfect vacuum or near vacuum laboratory, both of them will reach ground with same velocity this is because there is no resistance to their motion. This is always true no matter where you go and perform this experiment.
It can be easily proved from conservation of mechanical energy. Why conserving energy? because there are no forces acting on the freely falling objects other than conservative force(mg).
1,) C
2,) C
Hope this helps