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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.

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