Which of the following is a dimensionless quantity?

Question

Which of the following is a dimensionless quantity? (A) Magnetic flux density (B) Electric flux density (C) Lumen flux density (D) Optical density.

Tardigrade Admin · Accepted Answer

Optical density is the ratio of the speed of light in two media. As optical density is the ratio of two similar physical quantities, therefore it is the dimensionless quantity. All other given physical quantities have dimensions.

Q. Which of the following is a dimensionless quantity?

Magnetic flux density

Electric flux density

Lumen flux density

Optical density.

Optical density is the ratio of the speed of light in two media. As optical density is the ratio of two similar physical quantities, therefore it is the dimensionless quantity. All other given physical quantities have dimensions.