", "upvoteCount": 0, "url": "https://studymaterialcenter.in/question/moment-of-inertia-of-a-body-about-a-given-axis-is-1-5-kg-m-2-initially-the-body-is-at-rest-in-order-to-produce-a-rotational-kinetic-energy-of-1200-j-the-angular-acceleration-of-20-rad-s-2-must-be-appl/#acceptedAnswer" } } }
Moment of inertia of a body about a given axis is $1.5 \mathrm{~kg}$ $\mathrm{m}^{2}$. Initially the body is at rest. In order to produce a rotational kinetic energy of $1200 \mathrm{~J}$, the angular acceleration of $20 \mathrm{rad} / \mathrm{s}^{2}$ must be applied about the axis for a duration of:
$2.5 \mathrm{~s}$
$2 s$
$5 \mathrm{~s}$
JEE Main Previous Year Single Correct Question of JEE Main from Physics System of Particles and Rotational Motion chapter.
JEE Main Previous Year 9 Apr. 2019
A rod of length $L$ has non-uniform linear mass density given by $\rho(x)=a+b\left(\frac{x}{\mathrm{~L}}\right)^{2}$, where $a$ and $b$ are constants and $0 \leq x \leq \mathrm{L}$. The value of $x$ for the centre of mass of the rod is at:
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A uniform rectangular thin sheet $\mathrm{ABCD}$ of mass $\mathrm{M}$ has length a and breadth $b$, as shown in the figure. If the shaded portion HBGO is cut-off, the coordinates of the centre of mass of the remaining portion will be :
The position vector of the centre of mass $r_{\mathrm{cm}}$ of an asymmetric uniform bar of negligible area of crosssection as shown in figure is:
A force of $40 \mathrm{~N}$ acts on a point $\mathrm{B}$ at the end of an $\mathrm{L}$-shaped object, as shown in the figure. The angle $\theta$ that will produce maximum moment of the force about point $A$ is given by:
In a physical balance working on the principle of moments, when $5 \mathrm{mg}$ weight is placed on the left pan, the beam becomes horizontal. Both the empty pans of the balance are of equal mass. Which of the following statements is correct?