Question

plz help me solving this problem ​

Answer 1

a) clearly from the attached,we can say that,the actual direction of rain with the vertical is cos∅

This is obtained by explitting the velocity of rain in horizontal and vertical part

Hence option 4) is Right

B)Let the speed of the rain with respect to the ground be Vxi-j

velocity of man=ui

velocity of rain with respect to man=(Vxi-j)-ui

since the man is observing only the vertical component ,,this means horizontal component becomes zero

Vx-u=0

Vx=u

Now,when he doubles his speed,then his velocity with respect to the rain

=ui-j-2ui=-ui-j

in that case

Tan∅=-u/-1

1=ucot∅

putting this value,we get

velocity of rain with respect to the ground=ui-ucot∅j

velocity in maginitude of=(x^2+y^2)^1/2

=u(1+cot^2∅)^1/2

{hence option ii) is correct}

{hope it helps}