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Suppose the friction coefficient between...

Suppose the friction coefficient between the ground and the ladder of the previous problem is 0.540. Find the maximum weight of a mechanic who could go up and do the work from the same position of the ladder.

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The correct Answer is:
D
`mu=0.54, R_2=16g+mg, R_1=muR_2`
`rarr R_1xx10 cos 37^@=16gxx5xsin 37^@+mgxx8sin3^@`
`rarr 8R_1=48g+24/5mg`
`rarr R_2=(48g+24/5mg)/(8xx0.54)`

`rarr16g+mg=(240g+24mg)/(5x8x0.54)`
`rarr 16+m=(240+24m)/(40xx0.54)`
`rarr m=44kg`
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HC VERMA-ROTATIONAL MECHANICS-Exercises
  1. A uniform metre stick of mass 200 g is suspended from the ceiling thro...

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  2. A uniform ladder of length 10.0 m and mass 16.0 kg is resting against ...

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  3. Suppose the friction coefficient between the ground and the ladder of ...

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  4. A 6.5 m long ladder rests against as vertical wall reaching a height o...

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  5. the door of an almirah is 6 ft high, 1.5 ft wide and weights 8 kg. The...

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  6. A uniform rod of length L rests against a smooth roller as shown in fi...

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  7. A uniform rod of mass 300 g and length 50 cm rotates at a uniform angu...

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  8. A uniform square plate of mass 2.0 kg and edge 10 cm rotates about one...

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  9. Calculate the ratio of the angular momentum of the earth about its axi...

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  10. Two particles of masses m1 and m2 are joined by a light rigid rod of l...

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  11. A dumb bell consists of two identicasl small balls offmss 1/2 kg each ...

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  12. A wheel of moment of inertia 0.500 kg-m^2 and radius 20.0 cm is rotati...

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  13. A diver having a moment of inertia of 6.0 kg-m^2 about an axis through...

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  14. A boy is seated in a revolving chair revolving at an angular speed of ...

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  15. A boy is standing on a platform which is free to rotate about its axis...

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  16. A wheel of moment of inertia 0.10 kg-m^2 is rotating about a shaft at ...

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  17. A kid of mass M stands at the edge of a platform of radius R which can...

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  18. Suppose the platform of the previous problem is brought to rest with t...

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  19. Suppose the platform with the kid in the previous problem is rotting i...

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  20. A uniform rod of mass m and length l is struck at an end by a force F ...

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