Download App

6. system of particles and rotational motion — Physics STD 11 Science — Question

Rajasthan BoardEnglish MediumSTD 11 SciencePhysics6. system of particles and rotational motion1 Mark
MCQ
$A$ solid sphere with a velocity (of centre of mass) $v$ and angular velocity $\omega$ is gently placed on a rough horizontal surface. The frictional force on the sphere:
  • A
    must be forward (in direction of $v$)
  • B
    must be backward (opposite to $v$)
  • C
    cannot be zero
  • ✓
    none of the above
✓

Answer

Correct option: D.
none of the above
d
The sphere has a constant velocity and angular velocity, thus when it is placed on the surface no frictional force would act on it as there is no angular acceleration.

Without any acceleration there is no force involved and thus frictional force would be absent.

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

Explore more

More "M.C.Q (1 Marks)" from 6. system of particles and rotational motion→6. system of particles and rotational motion — all question types→Physics STD 11 Science question papers→Rajasthan Board STD 11 Science question papers→Rajasthan Board question paper generator→

Similar questions

$Assertion :$ The pressure of water reduces when it flows from a narrow pipe to a wider pipe.
$Reason :$ Since for wider pipe area is large, so flow of speed is small and pressure also reduces proportionately.
→
On a temperature scale $X$. The boiling point of water is $65^{\circ} X$ and the freezing point is $-15^{\circ} X$. Assume that the $X$ scale is linear. The equivalent temperature corresponding to $-95^{\circ} X$ on the Farenheit scale would be $..........^{\circ} F$
→
A train moves towards a stationary observer with speed $34 m/s$. The train sounds a whistle and its frequency registered by the observer is ${f_1}$. If the train’s speed is reduced to $17\, m/s$, the frequency registered is ${f_2}$. If the speed of sound is 340 m/s then the ratio ${f_1}/{f_2}$ is
→
Match List $I$ with List $II$ and select the correct answer using the codes given below the lists :

List $I$ List $II$
$P.$ Boltzmann constant $1.$ $\left[ ML ^2 T ^{-1}\right]$
$Q.$ Coefficient of viscosity $2.$ $\left[ ML ^{-1} T ^{-1}\right]$
$R.$ Planck constant $3.$ $\left[ MLT ^{-3} K ^{-1}\right]$
$S.$ Thermal conductivity $4.$ $\left[ ML ^2 T ^{-2} K ^{-1}\right]$

Codes: $ \quad \quad P \quad Q \quad R \quad S $ 

→
A Carnot's engine works as a refrigerator between $250\, K$ and $300\, K$. It receives $500\, cal$ heat from the reservoir at the lower temperature. The amount of work done in each cycle to operate the refrigerator is ..... $J$
→
Which one of the following energies cannot be possessed by a body at rest?
→

A block is left in the equilibrium position as shown in the figure.

If now it is stretched by $\frac{\text{mg}}{\text{k}}$, the net stretch of the spring is:

→
Two particles executing $S.H.M.$ of same frequency, meet at $x=+A / 2$, while moving in opposite directions. Phase difference between the particles is .........
→
From a building two balls $A$ and $B$ are thrown such that $A$ is thrown upwards and $B$ downwards (both vertically). If $v_{A}$ and $v_{B}$ are their respective velocities on reaching the ground, then
→
The $x$-t graph of a particle undergoing simple harmonic motion is shown below. The acceleration of the particle at $t=4 / 3 \mathrm{~s}$ is
→