Answer:
Force of static friction between the two surfaces
Explanation:
When two surfaces come into contact, they exert a force that resist the sliding of the two surfaces. This force is called static friction.
This force is given by the relation

Where,
μ - coefficient of static friction
η - normal force acting on the body
When a force acts on a body placed on a rough surface, it doesn't do any work if the applied force was less than the force of static friction.
So, in order to move the body, the applied force should be greater than the force of static friction.
A) 300cm/h
B)1 hr=60 min
300/60=5
5cm/min
C)1m=100cm
300/100=3
3m/h
Answer:
B) resistance
Explanation:
the resistance of a wire is proportional to its length, and inversely proportional to its cross-sectional area.
Answer:
<em>The K.E from A to B won't increase...</em>
Explanation:
That's because the P.E from A to B is increasing. The K.E will increase if charge moves from a higher potential to a lower potential i.e., from B to A.
That is the reason there is no effect on net K.E when moving from a potential to same potential over and over (A to C).