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A pebble of mass 0.05 kg is thrown verti...

A pebble of mass 0.05 kg is thrown vertically upwards Give the magnitude and direction of net force on the pebble (a) during its upward motion (b) during its downward motion (c) at the highest point where it is momentarily rest
Do your answers change if the pebble were thrown at an angle of say `45^(@)` horizontal direction lgnore air resistance .

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The only force in each case is the force of gravity, (neglecting effects of air) equal to 0.5 N vertically downward. The answers do not change, even if the motion of the pebble is not along the vertical. The pebble is not at rest at the highest point. It has a constant horizontal component of velocity throughout its motion.
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NCERT TAMIL-LAW OF MOTION-EXERCISE
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  2. A pebble of mass 0.05 kg is thrown vertically upwards Give the magnitu...

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  3. Give the magnitude and direction of the force acting on a stone of mas...

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  4. One end of a string of length 'l' is connected to a particle of m...

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  5. A constant retarding force of 50 N is applied to a body of mass 20 kg ...

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  6. A constant force acting on a body of mass 3 kg changes its speed from ...

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  7. A body of mass 5 kg is acted upon by two perpendicular forces 8 N and ...

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  9. A rocket with a lift off mass 20000 kg is blasted upwards with a net i...

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  10. A body of mass 0 .40 kg moving initially with a constant speed of 10 ...

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  12. A bob of mass 0.1 kg hung from the ceilling of a room by a string 2 m ...

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  16. Two masses 7 kg and 12 kg are connected at the two ends of a light ine...

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