UP Polytechnic Lecturer: Mechanical Paper -1 || Quiz 10

Two bars each of length L and of the same material are subjected to the same axial tensile force P. The first bar has a uniform diameter 2d. The second bar has a diameter d for length l and a diameter 2d for the remaining length. The ratio of the strain energies of the two bars U₁/U₂ is _________.

Which of the following sensor uses piezoelectric polyvinylidene fluoride (PVDF) for its manufacturing __________.

The acceleration of the piston at the position when the crank makes an angle of 90^o  with the line of slider is equal to

(Consider the length of connecting rod as 250 mm and crank radius as 50 mm)

where R is crank radius and  is angular velocity of crank

The ratio of the diameter of rivet hole to the pitch of rivet is 0.25, then the tearing efficiency of the joint is

A block of mass m rests on an inclined plane and is attached by a string to the wall as shown in the figure. The coefficient of static friction between the plane and the block is 0.25. The string can withstand a maximum force of 20 N. The maximum value of the mass (m) for which the string will not break and the block will be in static equilibrium is ____________ kg.
Take cosθ = 0.8 and sinθ = 0.6.
Acceleration due to gravity g = 10 m/s²