Which one of the following statements in the context of balancing in engines is correct?
1
Magnitude of the primary unbalancing force is less than the secondary unbalancing force
2
The primary unbalancing force attains its maximum value twice in one revolution of the crank
3
The hammer blow in the locomotive engines occurs due to unbalanced force along the line of stroke of the piston
4
The unbalanced force due to reciprocating masses varies in magnitude and direction