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

## Theory of Machine Oldham’s coupling is an inversion of the kinematic chain used in

Universal joint
Elliptical trammels
Rotary engine
Whitworth quick return mechanism

Lags by 90°
Is in phase

6 times more
2.44 times less
6 times less
2.44 times more

## Theory of Machine The frictional torque transmitted in a truncated conical pivot bearing, considering uniform wear, is

(1/2). μ W cosec α [(r₁³ - r₂³)/(r₁² - r₂²)]
(1/2). μ W cosec α (r₁ + r₂)
(2/3). μ W cosec α [(r₁³ - r₂³)/(r₁² - r₂²)]
(2/3).μ W cosec α (r₁ + r₂)

## 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 R/2
Become equal to 2R