JEE Mains · Physics · STD 11 - 6. system of particles and rotational motion
A triangular plate is shown. A force \(\overrightarrow{ F }=4 \hat{ i }-3 \hat{ j }\) is applied at point \(P\). The torque at point \(P\) with respect to point \('O'\) and \('Q'\) are
- A \(-15-20 \sqrt{3}, 15-20 \sqrt{3}\)
- B \(15+20 \sqrt{3}, 15-20 \sqrt{3}\)
- C \(15-20 \sqrt{3}, 15+20 \sqrt{3}\)
- D \(-15+20 \sqrt{3}, 15+20 \sqrt{3}\)
Answer & Solution
Correct Answer
(A) \(-15-20 \sqrt{3}, 15-20 \sqrt{3}\)
Step-by-step Solution
Detailed explanation
\(\overrightarrow{ F }=4 \hat{ i }-3 \hat{ j }\) \(\overrightarrow{ r }_{1}=5 \hat{ i }+5 \sqrt{3} \hat{ j } \& \overrightarrow{ r }_{2}=-5 \hat{ i }+5 \sqrt{3} \hat{j}\) Torque about \('O'\)…
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
- A metal exposed to light of wavelength \(800\,nm\) and emits photoelectrons with a certain kinetic energy. The maximum kinetic energy of photo-electron doubles when light of wavelength \(500\, nm\) is used. The work function of the metal is \(...eV\) (Take \(hc =1230 \,eV - nm\) ).JEE Mains 2022 Medium
- An upright object is placed at a distance of \(40\, cm\) in front of a convergent lens of focal length \(20\, cm\). A convergent mirror of focal length \(10\, cm\) is placed at a distance of \(60\, cm\) on the other side of the lens. The position and size of the final image will beJEE Mains 2019 Hard
- A stone of mass \(m\), tied to a string is being whirled in a vertical circle with a uniform speed. The tension in the string isJEE Mains 2022 Medium
- A solid sphere of mass \(2\,kg\) is making pure rolling on a horizontal surface with kinetic energy \(2240\,J\). The velocity of centre of mass of the sphere will be \(..........ms ^{-1}\).JEE Mains 2023 Medium
- The density and breaking stress of a wire are \(6 \times\) \(10^4 \mathrm{~kg} / \mathrm{m}^3\) and \(1.2 \times 10^8 \mathrm{~N} / \mathrm{m}^2\) respectively. The wire is suspended from a rigid support on a planet where acceleration due to gravity is \(\frac{1^{\text {rd }}}{3}\) of the value on the surface of earth. The maximum length of the wire with breaking is _______ \(\mathrm{m}\) (take, \(\mathrm{g}=\) \(\left.10 \mathrm{~m} / \mathrm{s}^2\right)\)JEE Mains 2024 Hard
- If \(10^{22}\) gas molecules each of mass \(10^{-26}\, kg\) collide with a surface (perpendicular to it)elastically per second over an area \(1\, m^2\) with a speed \(10^4\,m/s\), the pressure exerted by the gas molecules will be of the order ofJEE Mains 2019 Medium
More PYQs from JEE Mains
- Given below are two statements: Statement \(I\) : A uniform wire of resistance \(80\,\Omega\) is cut into four equal parts. These parts are now connected in parallel. The equivalent resistance of the combination will be \(5\,\Omega\). Statement \(II :\) Two resistance \(2\,R\) and \(3\,R\) are connected in parallel in a electric circuit. The value of thermal energy developed in \(3\,R\) and \(2\,R\) will be in the ratio \(3:2.\) In the light of the above statements, choose the most appropriate answer from the options given belowJEE Mains 2022 Medium
- The shortest distance between the lines \(x+1=2 y=-\) \(12 z\) and \(x=y+2=6 z-6\) isJEE Mains 2023 Easy
- Let \(a, b\) be two real numbers such that \(a b < 0\). If the complex number \(\frac{1+ ai }{ b + i }\) is of unit modulus and \(a+i b\) lies on the circle \(|z-1|=|2 z|\), then a possible value of \(\frac{1+[ a ]}{4 b }\), where \([ t ]\) is greatest integer function, is :JEE Mains 2023 Hard
- A vessel contains \(16 \,g\) of hydrogen and \(128 \,g\) of oxygen at standard temperature and pressure. The volume of the vessel in \(cm ^{3}\) isJEE Mains 2022 Medium
- An object of mass \(0.2 \mathrm{~kg}\) executes simple harmonic motion along \(\mathrm{x}\) axis with frequency of \(\left(\frac{25}{\pi}\right) \mathrm{Hz}\). At the position \(\mathrm{x}=0.04 \mathrm{~m}\) the object has kinetic energy \(0.5 \mathrm{~J}\) and potential energy \(0.4 \mathrm{~J}\) The amplitude of oscillation is _______ cm.JEE Mains 2024 Hard
- A passenger train of length \(60\, m\) travels at a speed of \(80\, km/hr\). Another freight train of length \(120\, m\) travels at a speed of \(30\, km/hr\). The ratio of times taken by the passenger train to completely cross the freight train when: \((i)\) they are moving in the same direction, and \((ii)\) in the opposite directions isJEE Mains 2019 Hard