Answer:
The statement "If a positively charged rod is brought close to a positively charged object, the two objects will repel
" applies to electric charges.
Explanation:
There are only two types of electric charges. Both having own magnitude but different charge.
1. Positive charge
2. Negative charge
Like charges repel each other and opposite charges always attract each other.
When a positively charged rod is brought close to a positively charged object, the rod and the object will repel.
Answer:
5. Quadruple
Explanation:
The electrostatic force between two charged particles is given by:

where
k is the Coulomb's constant
q1, q2 are the two charges
r is the separation between the charges
If the distance between the charges is reduced to half,

So the new force will be

So, the force will quadruple.
Answer:
When magnesium reacts with oxygen, it produces light bright enough to blind you temporarily. Magnesium burns so bright because the reaction releases a lot of heat. As a result of this exothermic reaction, magnesium gives two electrons to oxygen, forming powdery magnesium oxide (MgO).
Answer: Work W = 0
Explanation: Work W = F·s. Because rock does not move, s = 0 and
work done is zero.