Answer:
1. the force which can be felt or act only when two objects are in contact is known as contact force.
for example: frictional force, muscular force,
tension, air resistance .
2. the force which can be felt or act even when two objects are in contact or not is known as non-contact force.
for example: magnetic force, gravitational force, electrostatic force.
1) Equivalent resistance, 1/R = 1/15 + 1/40 + 1/60 = 8+3+2 /120 = 13/120
R = 120/13 = 9.23
2) Current, I = V/R = 115/9.23 = 12.45 A
