Question

write some situations swhere friction is undesirable

Answer 1

in machines, due to friction, wear n tear happens. this leads to formation of heat utilizing (a part of mechanical energy is converted to heat) which leads to decrease in efficiency of the machine. to prevent this, oiling is required.

Answer 2

the friction is undesirable in machines where the machines get over heat and worn out and there is lot of problem.so the auto mobile workers usr lubricants to decrease the friction.