JEE Mains · Physics · STD 11 - Transmission of heat
- JEE Mains 2023
- Medium
- MCQ
A bowl filled with very hot soup cools from \(98^{\circ}\,C\) to \(86^{\circ}\,C\) in \(2\) minutes when the room temperature is \(22^{\circ}\,C\). \(..........\,minutes\) long it will take to cool from \(75^{\circ}\,C\) to \(69^{\circ}\,C\) ?
Pick an option to check your answer.
Answer & Solution
Correct Answer
(B) \(1.4\)
Step-by-step Solution
Detailed explanation
\(\frac{\Delta Q }{\Delta t }=- K \left( T - T _0\right)\)
\(\frac{\Delta Q }{\Delta t }=- K \left( T _{ avg }- T _0\right)\)
\((i)\) \(\frac{ ms \times 12}{2}=- K \left(\frac{98+86}{2}-22\right)\)
\(6=-\frac{ K }{ ms }\left[\frac{98+86}{2}-22\right]\)
\(6=-\frac{ K }{ ms }[70]..........(i)\)
\((ii)\) \(\frac{ ms \times 6}{\Delta t }=- K \left(\frac{75+69}{2}-22\right)\) \(\frac{6}{\Delta t }=-\frac{ K }{ ms }(50) \ldots \ldots \ldots \ldots\) (ii)
\((ii)\) \(\div\) \((i)\)
\(\frac{6}{\Delta t (6)}=\frac{50}{70}\)
\(\Delta t =\frac{7}{5}=1.4\,min\)
More questions from Physics
- In a double slit experiment, when one of the slits is covered by a transparent mica sheet of refractive index \(1.56\), the central fringe shifts to the position of \(7^{th}\) bright fringe, obtained with both slits uncovered. If the light source wavelength is \(450\) nm, the thickness of mica sheet is \(\alpha \times 10^{-9}\) m. The value of \(\alpha\) is ______.JEE Mains 2026 Medium
- The de-Broglie wavelength of a particle having kinetic energy \(E\) is \(\lambda\). How much extra energy must be given to this particle so that the de-Broglie wavelength reduces to \(75 \,\%\) of the initial value ?JEE Mains 2021 Hard
- Consider an ideal gas confined in an isolated closed chamber. As the gas undergoes an adiabatic expansion, the average time of collision between molecules increases as \(V ^q\), where \(V\) is the volume of the gas. The value of \(q\) is \(\left( {\gamma = \frac{{{C_P}}}{{{C_V}}}} \right)\)JEE Mains 2015 Hard
- In the figure given, the electric current flowing through the \(5\, k \Omega\) resistor is \('x' mA.\) The value of \(x\) to the nearest integer is .........
JEE Mains 2021 Medium - A solid ball of radius \(R\) has a charge density \(\rho \) given by \(\rho = {\rho _0}\left( {1 - \frac{r}{R}} \right)\) for \(0 \leq r \leq R\). The electric field outside the ball isJEE Mains 2018 Hard
- The wavelength of the radiation emitted is \(\lambda_0\) when an electron jumps from the second excited state to the first excited state of hydrogen atom. If the electron jumps from the third excited state to the second orbit of the hydrogen atom, the wavelength of the radiation emitted will be \(\frac{20}{x} \lambda_0\). The value of \(x\) is \(........\)JEE Mains 2023 Medium
More PYQs from JEE Mains
- Formation of real image using a biconvex lens is shown below: If the whole set up is immersed in water without disturbing the object and the screen positions, what will one observe on the screen?
JEE Mains 2019 Medium - Two very long, straight and insulated wires are kept at \(90^o\) angle from each other In \(xy -\) plane as shown in the figure. These wires carry current of equal magnitude \(I\), whose directions are shown in the figure. The net magnetic field at point \(P\) will be
JEE Mains 2019 Medium - If the series limit frequency of the Lyman series is \(v_L\), then the series limit frequency of the \(P\)-fund series isJEE Mains 2018 Medium
- A coil of cross-sectional area \(A\) having \(n\) turns is placed in a uniform magnetic field \(B.\) When it is rotated with an angular velocity \(\omega ,\) the maximum \(e.m.f.\) induced in the coil will beJEE Mains 2018 Medium
- When \(M_1\) gram of ice at \(-10\,^oC\) (specific heat \(= 0.5\, cal\, g^{-1}\,^oC^{-1}\)) is added to \(M_2\) gram of water at \(50\,^oC\), finally no ice is left and the water is at \(0\,^oC\). The value of latent heat of ice, in \(cal\, g^{-1}\) isJEE Mains 2019 Medium