Ratio of inertia force to viscous force is known as

Consider the following statement for a ball falling in a viscous fluid: a) The viscous force is directly proportional to the radius of the ball b) The viscous force is directly proportional to the velocity of the ball c) The viscous force is inversely proportional to the radius of the ball d) The viscous force is inversely proportional to the velocity of the ball Which of the above statements are correct?

A

Both a and b are correct

B

Both a and d are correct

C

Both b and c are correct

D

Both c and d are correct

Read the given statements and conclusions carefully and select which of the conclusions follow(s) from the statements. Statements: I. All liquids are fluid. II. All fluids are viscous. Conclusions: I. All viscous are liquids. II. All liquids are viscous.

A

Only conclusion I follows

B

All the conclusions follow

C

Only conclusion II follows

D

No conclusion follows

The product of buoyant force and inertia force to the square of the viscous force is known as

A

Stanton number

B

Grashof number

C

Fourier number

D

Peclet number

The ratio of inertia force to viscous force is known as

A

Grashof number

B

Reynolds number

C

Fourier number

D

Nusselt number

Which of the following statements of D’Alembert’s principle are correct? 1. The net external force F actually acting on the body and the inertia force F1 together keep the body in a state of fictitious equilibrium. 2. The equation of motion may be written as F + (-ma) = 0 and the fictitious force (-ma) is called an inertia force. 3. It tends to give solution of a static problem an appearance akin to that of a dynamic problem.

A

1 and 3 only

B

1 and 2 only

C

2 and 3 only

D

1, 2 and 3

The ratio of the inertia force to the viscous force is called

A

Reynold's number

B

Froude's number

C

Weber's number

D

Euler's number

A torsional system with discs of moment of inertia $${I_1}$$ and $${I_2}$$ as shown in the below figure, is gear driven such that the ratio of speed of shaft B to shaft A is 'G'. Neglecting the inertia of gears, the equivalent inertia of disc on shaft B at the speed of shaft A is equal to
Theory of Machine mcq question image

A

$${\text{G}} \times {I_2}$$

B

$${{\text{G}}^2} \times {I_2}$$

C

$$\frac{{{I_2}}}{{\text{G}}}$$

D

$$\frac{{{I_2}}}{{{{\text{G}}^2}}}$$

Two identical synchronous machines with equal inertia constants are connected in parallel order and oscillating simultaneously. The effective inertia constant is 4 MJ / MVA. What will be the inertia constant of each machine?

A

2 MJ / MVA

B

16 MJ / MVA

C

4 MJ / MVA

D

8 MJ / MVA

The moment of inertia of a uniform sphere of radius, r about an axis passing through its centre is given by $$\frac{2}{5}\left( {\frac{{4\pi }}{3}{r^5}\rho } \right).$$ A rigid sphere of uniform mass density $$\rho $$ and radius R has two smaller spheres of radii $$\frac{R}{2}$$ hollowed out of it as shown in the figure given below.
Classical Mechanics mcq question image

The moment of inertia of the resulting body about Y-axis is

A

$$\frac{{\pi \rho {R^5}}}{4}$$

B

$$\frac{{5\pi \rho {R^5}}}{{12}}$$

C

$$\frac{{7\pi \rho {R^5}}}{{12}}$$

D

$$\frac{{3\pi \rho {R^5}}}{4}$$

Spherical balls of radius R are falling in a viscous fluid of viscosity Ƞ with a velocity v. The retarding viscous force acting on the spherical ball is ___________

A

Directly proportional to R but inversely proportional to v

B

Directly proportional to both radius R and velocity v

C

Inversely proportional to both radius R and velocity v

D

Inversely proportional to R but directly proportional to velocity v

Ratio of inertia force to viscous force is known as

Related Questions