Medium
Give an example of:
$(a)$ a physical quantity which has a unit but no dimensions
$(b)$ a physical quantity which has neither unit nor dimensions
$(c)$ a constant which has a unit
$(d)$ a constant which has no unit
$(a)$ a physical quantity which has a unit but no dimensions
$(b)$ a physical quantity which has neither unit nor dimensions
$(c)$ a constant which has a unit
$(d)$ a constant which has no unit
$(a)$ Plane angle $\theta = \frac{l}{r}$ has the unit radian, but its dimensional formula is $[M^{0} L^{0} T^{0}]$.
$(b)$ Strain $= \frac{\Delta l}{l} = \frac{\text{Change in length}}{\text{Original length}}$. It has neither a unit nor dimensions.
$(c)$ Gravitational constant $G = 6.67 \times 10^{-11} \text{ N} \cdot \text{m}^{2} \cdot \text{kg}^{-2}$. It is a constant with a unit.
$(d)$ Reynolds number $(Re)$ is a dimensionless constant.
$(b)$ Strain $= \frac{\Delta l}{l} = \frac{\text{Change in length}}{\text{Original length}}$. It has neither a unit nor dimensions.
$(c)$ Gravitational constant $G = 6.67 \times 10^{-11} \text{ N} \cdot \text{m}^{2} \cdot \text{kg}^{-2}$. It is a constant with a unit.
$(d)$ Reynolds number $(Re)$ is a dimensionless constant.
Explore More
Similar Questions
Match List-$I$ with List-$II$:
List-$I$ List-$II$ $(A)$ Young's Modulus $(I)$ $[ML^{-1}T^{-1}]$ $(B)$ Torque $(II)$ $[ML^{-1}T^{-2}]$ $(C)$ Coefficient of Viscosity $(III)$ $[M^{-1}L^3T^{-2}]$ $(D)$ Gravitational Constant $(IV)$ $[ML^2T^{-2}]$
Choose the correct answer from the options given below:
| List-$I$ | List-$II$ |
| $(A)$ Young's Modulus | $(I)$ $[ML^{-1}T^{-1}]$ |
| $(B)$ Torque | $(II)$ $[ML^{-1}T^{-2}]$ |
| $(C)$ Coefficient of Viscosity | $(III)$ $[M^{-1}L^3T^{-2}]$ |
| $(D)$ Gravitational Constant | $(IV)$ $[ML^2T^{-2}]$ |
Choose the correct answer from the options given below:
In the context of accuracy of measurement and significant figures in expressing results of experiment,which of the following is/are correct?
$(1)$ Out of the two measurements $50.14 \, cm$ and $0.00025 \, A$,the first one has greater accuracy.
$(2)$ If one travels $478 \, km$ by rail and $397 \, m$ by road,the total distance travelled is $478 \, km$.
$(1)$ Out of the two measurements $50.14 \, cm$ and $0.00025 \, A$,the first one has greater accuracy.
$(2)$ If one travels $478 \, km$ by rail and $397 \, m$ by road,the total distance travelled is $478 \, km$.
Medium
View SolutionMatch List-$I$ with List-$II$.
List-$I$ List-$II$ $(A)$ Coefficient of viscosity $(I)$ $[ML^0T^{-3}]$ $(B)$ Intensity of wave $(II)$ $[ML^{-2}T^{-2}]$ $(C)$ Pressure gradient $(III)$ $[M^{-1}LT^2]$ $(D)$ Compressibility $(IV)$ $[ML^{-1}T^{-1}]$
Choose the correct answer from the options given below:
| List-$I$ | List-$II$ |
| $(A)$ Coefficient of viscosity | $(I)$ $[ML^0T^{-3}]$ |
| $(B)$ Intensity of wave | $(II)$ $[ML^{-2}T^{-2}]$ |
| $(C)$ Pressure gradient | $(III)$ $[M^{-1}LT^2]$ |
| $(D)$ Compressibility | $(IV)$ $[ML^{-1}T^{-1}]$ |
Which of the following does not have the dimensions of force?
Easy
View Solution$Assertion$: In the measurement of physical quantities,direct and indirect methods are used.
$Reason$: The accuracy and precision of measuring instruments,along with errors in measurements,should be taken into account while expressing the result.
$Reason$: The accuracy and precision of measuring instruments,along with errors in measurements,should be taken into account while expressing the result.
Vedclass Products
For Students
Vedclass Test Series
Mock tests in real JEE/NEET style with performance analysis. 5-day free trial.
Start Free TrialFor Teachers
Exam Paper Generator
Generate Set A/B/C/D exam papers from 7.5L+ questions in 2 minutes. 3 chapters free.
Try FreeFor Institutes
Online Exam Module
Live online exams with unlimited students, 360° analytics & white-label branding.
See Demo