At Deoprayag (Garhwal, UP) river Alaknanda mixes with the river Bhagirathi and becomes river Ganga. Suppose Alaknand has a width of 12 m, Bhagirathi has a width of 8m and Ganga ha sa width of 16m. Assume that the depth of water is same in the three rivers. Let the average speed of water in Alaknanda be `20 kmh^-1` and in Bhagirathi be `16 kmh^-1`. Find the average speed of water in the river Ganga.

Answer

A, B, C

Explanation

Volume of water discharged from AlakN/Anda+Volum of water discharged from Bhagirathi= Volume of water Flow in Ganga.
let drarr `depth of 3 rivers
`rarr V_axxdxx12+V_Bxxdxx8`
`rarr V_Gxxdxx16`
[From equation of continuity]
`rarr 20xx12+16xx8=V_Gxx16`
`rarr V_Gxx16=368`
`rarr V_G=368/16`
`-=23km/hr`