Theory of Machine
The unbalanced force due to revolving masses

Constant in magnitude and direction both
Varies in direction but constant in magnitude
Varies in magnitude but constant in direction
Varies in magnitude and direction both

ANSWER DOWNLOAD EXAMIANS APP

Theory of Machine
Two heavy rotating masses are connected by shafts of lengths l₁, l₂ and l₃ and the corresponding diameters are d₁, d₂ and d₃. This system is reduced to a torsionally equivalent system having uniform diameter d = d₁ of the shaft. The equivalent length of the shaft is

l₁ + l₂ + l₃
l = l₁ + l₂.(d₁/d₂)³ + l₂.(d₁/d₃)³
(l₁ + l₂ + l₃)/3
l = l₁ + l₂.(d₁/d₂)⁴ + l₃.(d₁/d₃)⁴

ANSWER DOWNLOAD EXAMIANS APP

Theory of Machine
A rotor which is balanced statically but not dynamically is supported on two bearings L apart and at high speed of the rotor, reaction on the left bearing is R. The right side of the bearing is shifted to a new position 2L apart from the left bearing. At the same rotor speed, dynamic reaction on the left bearing in the new arrangement will

Remain same as before
Become equal to R/4
Become equal to 2R
Become equal to R/2

ANSWER DOWNLOAD EXAMIANS APP