JEE Mains · Physics · STD 11 - Fluid mechanics
- JEE Mains 2014
- Medium
- Numerical
An open glass tube is immersed in mercury in such a way that a length of \(8\ cm\) extends above the mercury level. The open end of the tube is then closed and sealed and the tube is raised vertically up by additional \(46\ cm\). What will be length of the air column above mercury in the tube now ....... \(cm\) ? ( Atmospheric pressure = \(76\ cm\) of \(Hg\))
Pick an option to check your answer.
Answer & Solution
Correct Answer
(D) \(16 \)
Step-by-step Solution
Detailed explanation
Length of the air column above mercury in the tube is,
\(p + x = {P_0}\)
\( \Rightarrow p = \left( {76 - x} \right)\)
\( \Rightarrow 8 \times A \times 76 = \left( {76 - x} \right) \times A \times \left( {54 - x} \right)\)
\(\therefore \,x = 38\)
Thus, lenght of air column \(=54-38=16\,cm.\)
More questions from Physics
- Two coils, \(X\) and \(Y\), are kept in close vicinity of each other. When a varying current, \(I(t)\), flows through coil \(X\), the induced emf \((V(t))\) in coil \(Y\), varies in the manner shown here. The variation of \(I(t)\); with time, can then be represented by the graph labelled as graph
JEE Mains 2013 Medium - A battery of \(3.0\, V\) is connected to a resistor dissipating \(0.5\, W\) of power. If the terminal voltage of the battery is \(2.5\, V\) the power dissipated within the internal resistance is\(.......W\)JEE Mains 2020 Hard
- When a car is at rest, its driver sees rain drops falling on it vertically. When driving the car with speed \(v,\) he sees that rain drops are coming at an angle \(60^{\circ}\) from the horizontal. On further increasing the speed of the car to \((1+\beta) v ,\) this angle changes to \(45^{\circ} .\) The value of \(\beta\) is close to\(......\)JEE Mains 2020 Hard
- In finding the electric field using Gauss Law the formula \(|\overrightarrow{\mathrm{E}}|=\frac{q_{\mathrm{enc}}}{\varepsilon_{0}|\mathrm{A}|}\) is applicable. In the formula \(\varepsilon_{0}\) is permittivity of free space, \(A\) is the area of Gaussian surface and \(q_{enc}\) is charge enclosed by the Gaussian surface. The equation can be used in which of the following situation?JEE Mains 2020 Medium
- A series \(L C R\) circuit has \(L=0.01\,H, R=10\,\Omega\) and \(C =1\,\mu F\) and it is connected to ac voltage of amplitude \(\left( V _{ m }\right) 50\,V\). At frequency \(60 \%\) lower than resonant frequency, the amplitude of current will be approximately \(...............\,mA\)JEE Mains 2022 Hard
- In a double slit experiment the distance between the slits is 0.1 cm and the screen is placed at 50 cm from the slits plane. When one slit is covered with a transparent sheet having thickness \(t\) and refractive index \(n (=1.5)\), the central fringe shifts by 0.2 cm . The value of t is _________ cm .JEE Mains 2026 Easy
More PYQs from JEE Mains
- Light is incident from a medium into air at two possible angles of incidence \((A)\, 20^o\) and \((B)\, 40^o\) . In the medium light travels \(3.0\, cm\) in \(0.2\, ns\). The ray willJEE Mains 2013 Hard
- One end of a straight uniform \(1\; \mathrm{m}\) long bar is pivoted on horizontal table. It is released from rest when it makes an angle \(30^{\circ}\) from the horizontal (see figure). Its angular speed when it hits the table is given as \(\sqrt{\mathrm{n}}\; \mathrm{s}^{-1},\) where \(\mathrm{n}\) is an integer. The value of \(n\) is
JEE Mains 2020 Medium - For a transverse wave travelling along a straight line, the distance between two peaks (crests) is \(5 \,m ,\) while the distance between one crest and one trough is \(1.5 \,m\) The possible wavelengths (in \(m\) ) of the waves areJEE Mains 2020 Easy