Theory of Machine
A shaft has two heavy rotors mounted on it. The transverse natural frequencies, considering each of the rotor separately, are 100 Hz and 200 Hz respectively. The lowest critical speed is

9,360 r.p.m.
6,000 r.p.m.
5,367 r.p.m.
12,000 r.p.m.

ANSWER DOWNLOAD EXAMIANS APP

Theory of Machine
Hammer blow

Varies inversely with the square of the speed
Is the maximum horizontal unbalanced force caused by the mass provided to balance the reciprocating masses.
Is the maximum vertical unbalanced force caused by the mass added to balance the reciprocating masses
Varies as the square root of the speed

ANSWER DOWNLOAD EXAMIANS APP