6. Surface Tension is due to-

A. Cohesion

B. Adhesion

C. Viscous force

D. the difference between cohesive and adhesive forces

Click for Answer/Explanation

Correct Answer is A

Read More- Theory of Machine Objective Questions

7. The least radius of gyration of a ship is 9 m and the meta-centric height is 750 mm. Find the time period of the oscillation of the ship?

A. 20.85 seconds

B. 42.41 seconds

C. 75.4 seconds

D. 85 seconds

Click for Answer/Explanation

Correct Answer is A

Using the formula

T = [2πv(K²/g × GM)]

where K is the radius of gyration

8. When pressure drag over a body is large as compared to the friction drag, then the shape of the body is that of –

A. a bluff body

B. an aerofoil

C. a streamlined body

D. a 2-dimensional body

Click for Answer/Explanation

Correct Answer is A

9. A block of aluminum having the mass of 12 kg is suspended by a wire and lowered until submerged into a tank containing oil of relative density 0.8. Taking the relative density of aluminum as 2.4, the tension in the wire will be (take g = 10 m/s²)?

A. 120 N

B. 80 N

C. 800 N

D. 1200 N

Click for Answer/Explanation

Correct Answer is B

The volume of Al = 12/2.4

T + Buoyant Force = mg —-(Eq. 1)

Buoyant Force = ρ × Vol. of Al × g

Now, Put the value of the Buoyant Force in Eqn. 1 and get the Tension developed in the wire.

10. Streamline, path line and streakline are identical when the –

A. flow is steady

B. flow is uniform

C. flow is neither steady nor uniform

D. flow velocities do not change steadily with time

Click for Answer/Explanation

Correct Answer is A

Please Comment Below