Q.3 Fill in the blanks in the following statements.
(a) To draw water from a well we have to ______ at the rope.
(b) A charged body ______ an uncharged body towards it.
(c) To move a loaded trolley we have to ______ it.
(d) The north pole of a magnet _______ the north pole of another magnet.

(a) To draw water from a well we have to pull at the rope.

(b) A charged body attracts an uncharged body towards it.

(c) To move a loaded trolley we have to pull or push it.

(d) The north pole of a magnet repels the north pole of another magnet.

EXPLANATION

1) Pull is a force which helps to counteract the gravitational force of the earth. Water can be pulled upwards when the weight of water drawn is less than the applied pull by the individual. That means if the force with which the earth pulls the same amount of water( weight of water drawn) by means of gravitational force in the downward direction, is less than the muscular force with which an individual pulls the same amount of water upwards, then only the water can be pulled out.

2) A charged body attracts an uncharged body by oppositely charging it. That means, if the charged body is positively charged( lose of electrons) then it converts the uncharged body into negatively charged body and then undergoes attraction. And if the charged body is negatively charged(gain of electrons) then it converts the uncharged body into positively charged body and then undergoes attraction.

3) To move a loaded trolley, we have to overcome the frictional force of the ground by applying a muscular force of magnitude greater than the magnitude of the frictional force. This muscular force can be a push or a pull.

4) As we know that like poles repel each other while unlike poles attract each other. Hence north pole of one magnet repels the north pole of the other magnet.