Determining Speed & Angle of Raindrops Relative to Ground

Join the discussion
Registration is free. Ask a follow-up in this thread, or start your own.
1 reply · 4K views
laxman31757
Messages
1
Reaction score
0
While driving North at 25 m/s during a rainstorm you notice that the rain makes an angle of 38 degrees with the vertical. while driving back home moments later at the same speed but in the opposite direction, you see that the rain is falling straight down. From these observations, determine the speed and angel of the raindrops relative to the ground.

i have no clue how to even start this
 
Physics news on Phys.org
Welcome to PF!

laxman31757 said:
While driving North at 25 m/s during a rainstorm you notice that the rain makes an angle of 38 degrees with the vertical. while driving back home moments later at the same speed but in the opposite direction, you see that the rain is falling straight down. From these observations, determine the speed and angel of the raindrops relative to the ground.

Hi laxman31757! Welcome to PF! :smile:

This is a vector addition problem …

velocities are vectors, so you can combine them using a vector triangle …

write Vcg for the velocity of the car relative to the ground,

Vrg for the velocity of the rain relative to the ground,

and Vrc for the velocity of the rain relative to the car …

so make a triangle, with an arrow along each side (and be careful to join the sides so that the arrows join correctly!) :smile: