Theory of Machine The efficiency of a screw jack is maximum, when (where α = Helix angle, and φ = Angle of friction) α = 45° - φ/2 α = 45° + φ/2 α = 90° + φ α = 90° - φ α = 45° - φ/2 α = 45° + φ/2 α = 90° + φ α = 90° - φ ANSWER DOWNLOAD EXAMIANS APP
Theory of Machine In an open pair, the two elements of a pair Are not held together mechanically Have a surface contact when in motion Are kept in contact by the action of external forces, when in motion Have a line or point contact when in motion Are not held together mechanically Have a surface contact when in motion Are kept in contact by the action of external forces, when in motion Have a line or point contact when in motion ANSWER DOWNLOAD EXAMIANS APP
Theory of Machine A disc is a spinning with an angular velocity ω rad/s about the axis of spin. The couple applied to the disc causing precession will be (where I = Mass moment of inertia of the disc, and ωP = Angular velocity of precession of the axis of spin) (1/2). I ω ωP Iω² (1/2).Iω² I ω ωP (1/2). I ω ωP Iω² (1/2).Iω² I ω ωP ANSWER DOWNLOAD EXAMIANS APP
Theory of Machine When the pitching of a ship is __________ the effect of gyroscopic couple acting on it will be to move the ship towards port side. Backward Downward Forward Upward Backward Downward Forward Upward ANSWER DOWNLOAD EXAMIANS APP
Theory of Machine One end of a helical spring is fixed while the other end carries the load W which moves with simple harmonic motion. The frequency of motion is given by (where δ = Deflection of the spring) 1/2π. √(g/δ) 2π. √(g/δ) 1/2π. √(δ/g) 2π. √(δ/g) 1/2π. √(g/δ) 2π. √(g/δ) 1/2π. √(δ/g) 2π. √(δ/g) ANSWER DOWNLOAD EXAMIANS APP
Theory of Machine Whitworth quick return mechanism is obtained by inversion of Kinematic chain Five link mechanism Roller cam mechanism Slider crank mechanism Kinematic chain Five link mechanism Roller cam mechanism Slider crank mechanism ANSWER DOWNLOAD EXAMIANS APP