JEE Mains · Physics · STD 11 - 1. units,dimensions and measurement
Which of the following is not a dimensionless quantity?
- A Relative magnetic permeability \(\left(\mu_{{r}}\right)\)
- B Power factor
- C Permeability of free space \(\left(\mu_{0}\right)\)
- D Quality factor
Answer & Solution
Correct Answer
(C) Permeability of free space \(\left(\mu_{0}\right)\)
Step-by-step Solution
Detailed explanation
\(\left[\mu_{{}}\right]=1 \text { as } \mu_{{r}}=\frac{\mu}{\mu_{{m}}}\) [power factor \((\cos \phi)]=1\) \(\mu_T{0}=\frac{{B}_{0}}{{H}}\left(\right.\) unit \(\left.={NA}^{-2}\right)\) : Not dimensionless \(\left[\mu_{0}\right]=\left[{MLT}^{-2} {A}^{-2}\right]\) quality factor…
See the Complete Solution
Get step-by-step explanations for this and 2.5 Lakh+ more JEE, NEET & CET questions.
- Unlock all solutions
- Practice the full chapter
- Track accuracy across PYQs
4.8 rated on Google Play · 14,000+ reviews
More questions from Physics
- When a certain photosensitive surface is illuminated with monochromatic light of frequency \(v\) , the stopping potential for the photo current is \(-V_0/2.\) When the surface is illuminated by monochromatic light of frequency \(v/2,\) the stopping potential is \(-V_0.\) The threshold frequency for photoelectric emission isJEE Mains 2019 Medium
- If a satellite orbiting the Earth is 9 times closer to the Earth than the Moon, what is the time period of rotation of the satellite? Given rotational time period of Moon \(=27\) days and gravitational attraction between the satellite and the moon is neglected.JEE Mains 2025 Medium
- \(100\) balls each of mass moving with speed \(v\) simultaneously strike a wall normally and reflected back with same speed, in time \(t s\). The total force exerted by the balls on the wall isJEE Mains 2023 Medium
- \(ABC\) is a plane lamina of the shape of an equilateral triagnle. \(D,\) \(E\) are mid points of \(AB\), \(AC\) and \(G\) is the centroid of the lamina. Moment of inertia of the lamina about an axis passing through \(G\) and perpendicular to the plane \(ABC\) is \(I _{0} .\) If part \(ADE\) is removed, the moment of inertia of the remaining part about the same axis is \(\frac{ NI _{0}}{16}\) where \(N\) is an integer. Value of \(N\) is
JEE Mains 2020 Hard - A straight rod of length \(L\) extends from \(x = a\) to \(x = L + a\). The gravitational force it exerts on a point mass \(‘m’\) at \(x = 0\), if the mass per unit length of the rod is \(A + Bx^2\), is given byJEE Mains 2019 Hard
- In a hydraulic lift, the surface area of the input piston is \(6 \mathrm{~cm}^2\) and that of the output piston is \(1500 \mathrm{~cm}^2\). If 100 N force is applied to the input piston to raise the output piston by 20 cm, then the work done is _______ kJ.JEE Mains 2025 Medium
More PYQs from JEE Mains
- A parallel-plate capacitor of capacitance \(40 \mu \mathrm{~F}\) is connected to a 100 V power supply. Now the intermediate space between the plates is filled with a dielectric material of dielectric constant \(\mathrm{K}=2\). Due to the introduction of dielectric material, the extra charge and the change in the electrostatic energy in the capacitor, respectively, areJEE Mains 2025 Medium
- An object of mass 1000 g experiences a time dependent force \(\vec{F}=\left(2 t \hat{i}+3 t^2 \hat{j}\right) N\). The power generated by the force at time \(t\) is :JEE Mains 2025 Medium
- The mean of the coefficients of \(x, x^2, \ldots \ldots x ^7\) in the binomial expansion of \((2+x)^9\) is \(...........\).JEE Mains 2023 Hard
- Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R
Statement I: Change in internal energy of a system containing \(n\) mole of ideal gas can be written as \(\Delta U = n C_v (T_f - T_i) = \dfrac{nR}{\gamma - 1}(T_f - T_i)\), where \(\gamma = \dfrac{C_p}{C_v}\), \(T_i =\) initial temperature, \(T_f =\) final temperature.
Statement II: Relation between degree of freedom \(f\) and \(\gamma (= C_p/C_v)\) is \(\left(\gamma = 1 + \dfrac{2}{f}\right)\)
Choose the correct answer from the options given belowJEE Mains 2026 Medium - A screw gauge with a pitch of \(0.5 \ mm\) and a circular scale with \(50\) divisions is used to measure the thickness of a thin sheet of Aluminium. Before starting the measurement, it is found that wen the two jaws of the screw gauge are brought in contact, the \(45^{th} \)division coincides with the main scale line and the zero of the main scale is barely visible. What is the thickness of the sheet (in \(mm\)) if the main scale reading is \(0.5\ mm\) and the \(25^{th}\) division coincides with the main scale lineJEE Mains 2016 Medium
- For a plane electromagnetic wave, the magnetic field at a point \(x\) and time \(t\) is \(\overrightarrow{ B }( x , t )=\left[1.2 \times 10^{-7} \sin \left(0.5 \times 10^{3} x +1.5 \times 10^{11} t \right) \hat{ k }\right] T\) The instantaneous electric field \(\overrightarrow{ E }\) corresponding to \(\overrightarrow{ B }\) is : (speed of light \(\left.c=3 \times 10^{8} ms ^{-1}\right)\)JEE Mains 2020 Medium