MCQ
If $I = 50\, kg-m^2$, then ......... $N-m$ torque will be applied to stop it in $10\, sec$. Its initial angular speed is $20\, rad/sec$.
  • $100$
  • B
    $150$
  • C
    $200$
  • D
    $250$

Answer

Correct option: A.
$100$
a
$\tau=\mathrm{I} \alpha=\frac{\mathrm{I} \Delta \mathrm{W}}{\Delta \mathrm{t}}=\frac{50(0-20)}{10}$

$\tau=-100 \mathrm{N}-\mathrm{m}$ means

$100 \mathrm{N}-\mathrm{m}$ in opposite to angular speed.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

In Young's double slit experiment, monochromatic light of wavelength $5000$ $A$ is used. The slits are $1.0 \mathrm{~mm}$ apart and screen is placed at $1.0 \mathrm{~m}$ away from slits. The distance from the centre of the screen where intensity becomes half of the maximum intensity for the first time is___________ $10^{-6} \mathrm{~m}$.
The de$-$Broglie wavelength of electron in $3^{\text {rd }}$ orbit of $He ^{+1}$ ion is approximately (in $A^{\circ}$)
The de-Broglie wavelength of an electron having $80eV$ of energy is nearly .............. $\mathop {\rm{A}}\limits^o $ ($1eV = 1.6 ×10^{-19} J$, Mass of electron $= 9 ×10^{-31} kg$ Plank’s constant $= 6.6 × 10^{-34}$ $J-sec$)
The lead wires should have
A particle of charge $Q$ and mass $M$ moves in a circular path of radius $R$ in a uniform magnetic field of magnitude $B$. The same particle now moves with the same speed in a circular path of same radius $R$ in the space between the cylindrical electrodes of the cylindrical capacitor. The radius of the inner electrode is $R/2$ while that of the outer electrode is $ 3R/2.$ Then the potential difference between the capacitor electrodes must be
On all the six surfaces of a unit cube, equal tensile force of $F$ is applied. The increase in length of each side will be ($Y =$ Young's modulus, $\sigma $= Poission's ratio)
If a solid sphere of mass $5\,kg$ and a disc of mass $4\,kg$ have the same radius. Then the ratio of moment of inertia of the disc about a tangent in its plane to the moment of inertia of the sphere about its tangent will be $\frac{x}{7}$. The value of $x$ is $.........$
A cyclist on a level road takes a sharp circular turn of radius $3 \;m \;\left( g =10 \;ms ^{-2}\right)$. If the coefficient of static friction between the cycle tyres and the road is $0.2$, at which of the following speeds will the cyclist not skid while taking the turn?
A closed organ pipe (closed at one end) is excited to support the third overtone. It is found that air in the pipe has
An oscillator circuit consists of an inductance of 0.5mH and a capacitor of $20\ , \mu F$. The resonant frequency of the circuit is nearly......$Hz$