Q21 of 43 Page 85

Rain is falling vertically with a speed of 35 ms–1. A woman rides a bicycle with a speed of 12 ms–1 in the east to west direction. In which direction should she hold her umbrella?

Velocity of raindrops =

The velocity of women =


Here x-axis is defined from west to east and y-axis along up and down direction.



Angle between and is 90°


Let V be the resultant; then it will be calculated as under:






Also,


So, the women must hold the umbrella at an angle 18.92° with the vertical and towards forward.


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