A child is sitting on a swing.Its minimum and maximum heights from the ground are 0.75 m and 2m respectively. Its maximum speed will be :

A child is sitting on a swing.Its minimum and maximum heights from the

1.	A child is sitting on a swing.Its minimum and maximum heights from the ground are 0.75 m and 2m respectively. Its maximum speed will be :
Answer» 10 m/s 8 m/s 5 m/s 15 m/s Solution :Here effective height `h=2-0.75=1.25` m. Now `(1)/(2)MV^(2)="mgh"impliesv=SQRT(2gh)` `=sqrt(2xx10xx1.25)=5` m/s. `:.` CORRECT CHOICE is ( c )

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A child is sitting on a swing.Its minimum and maximum heights from the ground are 0.75 m and 2m respectively. Its maximum speed will be :

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