Question

If \( d_p \) is the equivalent diameter of a non-spherical particle, \( V_p \) its volume and \( S_p \) its surface area, then its sphericity \( \Phi_s \) is defined by

• A. \( \Phi_s = \frac{6 V_p}{d_p S_p} \)
• B. \( \Phi_s = \frac{V_p}{d_p S_p} \)
• C. \( \Phi_s = 6 d_p S_p \)
• D. \( \Phi_s = \frac{d_p S_p}{V_p} \)

Hint:

Sphericity helps relate real particle shapes to spheres for simplified calculations.

Answer 1

The Correct Option is A

Sphericity is a measure of how spherical a particle is.
It is defined as the ratio of surface area of a sphere (with same volume) to the actual particle surface area.
Using formula: \( \Phi_s = \frac{\text{Surface area of sphere with } V_p}{S_p} = \frac{6 V_p}{d_p S_p} \)