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A small block is rotating in a horizonta...

A small block is rotating in a horizontal circle at the end of a thread which passes down through a hole at the centre of table top. If the system is rotating at 2.5 rps in a circle of 30 cm radius, what will be the speed of rotation when the thread is pulled inwards to decrease the radius to 10 cm ? Neglect friction.

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SL ARORA-System of particles & rotational Motion-EXERCISE
  1. A small block is rotating in a horizontal circle at the end of a threa...

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  2. Two bodies of masses 1 kg and 2 kg are located at (1,2) and (-1,3), r...

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  3. The distance between the centres of carbon and oxygen atoms in the car...

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  4. Three blocks of uniform thickness and masses m, m and 2m are placed at...

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  5. Find the centre of mass of three particle at the vertices of an equila...

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  6. A gridstone has a constant acceleration of 4 rad s^-1. Starting from r...

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  7. The speed of a motor increases from 600 rpm to 1200 rpm in 20 s. What ...

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  8. On the application of a constant torque, a wheel is turned from rest t...

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  9. The motor of an engine is erotating about its axis with an angular vel...

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  10. A car is moving at a speed of 72 kmh^(-1). The diameter of its wheel i...

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  11. A wheel starting from rest via rotating with a constant angular veloci...

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  12. Determine the angular momentum of a car of mass 1500 kg moving in a ci...

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  13. Mass of an electron is 9.0xx10^(-31) kg. It revolves around the nucleu...

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  14. Find the moment fo inertia of the hydrogen molecules about an axis pas...

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  15. Three particles each of mass 100 g are placed at the vertices of an eq...

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  16. Four point masses of 20 g each are placed at the corners of a square A...

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  17. The point masses of 0.3 kg, 0.2 kg and 0.1 kg are placed at the corner...

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  18. Three particles of masses 0.50 kg, 1.0 kg and 1.5 kg are placed at the...

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  19. Three particles, each of mass m are situated at the vertices of an equ...

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  20. Four particles each of mass m are kept at the four corners of a square...

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  21. What is the moment of inertia of a ring of mass 2kg and radius 50 cm a...

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