Home
Class 12
PHYSICS
A wire is wrapped N times over a solid s...

A wire is wrapped N times over a solid sphere of mass m which is place on a smooth horizontal surface. A horizontal magnetic field of induction `vec B` is present. Find the (a) torque (b) angular acceleration experienced by the sphere. Assume that the mass of the wire is negligible compared to the mass of the sphere.

Text Solution

Verified by Experts

The correct Answer is:
`07.85`

As the sphere is free to rotate, it must rotate about the centroidal axis.
`rArr alpha=(bartau)/(I_(c ))`
`alpha=(barmu xx barB)/(I_(c )) = (-(NiA)hatj xx Bhati)/((2)/(3)MR^(2))`
`=(5Ni(piR^(2))B hatk)/(2MR^(2))`
`=(5)/(2) xx pi ((NiB)/(M))`
`:.alpha=(7.85 NiB hatk)/(M)`
Promotional Banner

Topper's Solved these Questions

  • NTA TPC JEE MAIN TEST 47

    NTA MOCK TESTS|Exercise PHYSICS (SUBJECTIVE NUMERICAL)|10 Videos

  • NTA TPC JEE MAIN TEST 46

    NTA MOCK TESTS|Exercise PHYSICS|30 Videos

  • NTA TPC JEE MAIN TEST 48

    NTA MOCK TESTS|Exercise PHYSICS |29 Videos

Similar Questions

Explore conceptually related problems

A solid sphere of radius R is placed on a smooth horizontal surface. A horizontal force F is applied at height h from the lowest point. For the maximum acceleration of the centre of mass

A solid sphere of mass ma nd radis R is placed on a rough horizontal surface A horizontal force F is applied to sphere at a height h, (0lehleR) from centre. If sphere rolls slipping then,

A solid sphere of radius R lies on a smooth horizontal surface. It is pulled by a horizontal force acting tangentially from the highest point. Find the distance traveled by the sphere during the times it makes one rotation.

Two equal spheres of mass m are in contact on a smooth horizontal table. A third identical sphere impinges symmetrically on them and reduces to rest. Then:

A sphere of mass m and radius r is placed on a rough plank of mass M . The system is placed on a smooth horizontal surface. A constant force F is applied on the plank such that the sphere rolls purely on the plank. Find the acceleration of the sphere.

A solid sphere of mass m and radius R is placed over a plank of same mass m . There is sufficient friction between sphere and plank to prevent slipping. Angular acceleration of sphere is

Consider the system shown. A solide sphere (of mass m and radius R) is placed over a plak (of mass 2m and placed over a smooth horizontal surface.) A horizontal force F is applied at the top of the sphere, as shown. Consider that the friction between the sphere and plank is sufficient enough for no slipping of the sphere over then plank. Friction force acting between the sphere and the plank is