Concepts Of Physics MCQ Edition [Volume 1]
- Exam
- Concepts Of Physics MCQ Edition [Volume 1]
- Subject
- Physics
- Chapter
- Introduction to Physics
Concepts Of Physics MCQ Edition [Volume 1] · Physics · Introduction to Physics
Determine if the following equation is dimensionally correct: =...
Determine if the following equation is dimensionally correct:
where height, surface tension, density, pressure, volume, coefficient of viscosity, frequency and moment of inertia.
where height, surface tension, density, pressure, volume, coefficient of viscosity, frequency and moment of inertia.
Options
- AThe equation is dimensionally incorrect, as the right side has dimensions of .
- BThe equation is dimensionally correct.
- CThe equation is dimensionally incorrect, as the right side is dimensionless.
- DThe equation is dimensionally incorrect, as the right side has dimensions of .
Correct answer
B. The equation is dimensionally correct.
Step-by-step solution
Dimensions of the left hand side (LHS):
Dimensions of the terms on the right hand side (RHS):
Substituting these into the expression under the square root:
\left[\dfrac{mgl}{I}\right] = \dfrac{[M][L T^{-2}][L]}{[M L^2]} = [T^{-2}]
Since the dimensions of the LHS and RHS are equal, the equation is dimensionally correct.
Dimensions of the terms on the right hand side (RHS):
Substituting these into the expression under the square root:
\left[\dfrac{mgl}{I}\right] = \dfrac{[M][L T^{-2}][L]}{[M L^2]} = [T^{-2}]
Since the dimensions of the LHS and RHS are equal, the equation is dimensionally correct.