Engineering Analysis

If there are 7 physical variables and 3 fundamental dimensions, how many numbers of pi terms shall be considered?

• 1

• 2

• 3

• 4

Which equation is not dimensionally correct?

What is the dimension of dynamic viscosity?

What is the dimension of energy?

In a dimensional form, the radius of blast in a nuclear wave shock wave is dependent on energy (E), ambient density (ρ) and time (T).

What is the correct Rayleigh's form for the above scenario.

What is the Pi 1 term of the relationship that exists between pressure drop (∆P) and other variables such as diameter (d), length (L), density (ρ), dynamic viscosity (μ) and velocity (v).

Repeating Variables: d, ρ, μ

𝑐 + 1 = 0 − − − − − − (1)

𝑎 + 𝑏 − 3𝑐 + 1 = 0 − −(2)

− 𝑏 − 2 = 0 − − − − (3)

• a = 2, b = 2, c= 1

• 𝑎 = −2, 𝑏 = −2, 𝑐 = −1

• a= 1, b= -1 c= 1

• a = 2, b = -2, c= 1

What is not a Primary Dimension?

• Mass

• Length

• Electric Current

• Density

The resistance to motion ‘R’ for a sphere having diameter ‘D’ moving at constant velocity ‘v’ through a compressible fluid is dependent upon the density ‘𝜌’ and the bulk modulus ‘K’ of the fluid. The resistance is primarily due to compression of the fluid in front of the sphere.

For the above scenario what can not be selected as a Repeating Variable

• D

• K

• v

• R