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प्रश्न
It takes 20 s for a person A of mass 50 kg to climb up the stairs, while another person B of same mass does the same in 15 s. Compare the power developed by the persons A and B.
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उत्तर
Power developed by the persons A and B is
`p_1/p_2 = ((mgh)/t_1)/((mgh)/t_2) = t_2/t_1 = 15/20 = 3:4`
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संबंधित प्रश्न
Differentiate between work and power.
A body, when acted upon by a force of 10 kgf, gets displaced by 0.5 m. Calculate the work done by the force, when the displacement is (i) in the direction of force, (ii) at an angle of 60° with the force, and (iii) normal to the force. (g = 10 N kg-1)
State the condition when a force produces
(i) linear motion.
(ii) rotational motion, in a body.
State the principle of moments.
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`["Hint" : "Efficiency" = "useful power"/"power input"]`
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A force of 1 kgf displaces a body by a distance of 10 cm
(i) in direction of force,
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(iii) at an angle of 60° to the direction of the force.
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