If there is no wind blowing, rain falls vertically at 9 metres per second.
The wind blowing makes the rain come down at an angle.
Joe and Kerry measure the angle of the falling rain at the same time. To Joe, the rain appears to be falling towards the east at an angle of 51 degrees to the vertical. To Kerry, the rain appears to be falling towards the south at an angle of 32 degrees to the vertical.
Find the speed of the wind.
How do you get started with this question?
Replied to MT3
Hi GeoNerd,
Have you tried drawing a diagram?
First of all, sketch a diagram. (tetrahedron)
Draw a vertical line AB to represent the vertical and label it 9m/s.
From A draw a line AJ at 51° to AB to the East to represent the rain as Joe sees it.
From A draw a line AK at 32° to AB to the South to represent the rain as Kerry sees it.
The triangle KBJ on the ‘ground’, has a right-angle at B as BJ is East and BK is South.
Use Δ ABJ to find BJ using trig and ΔABK to find BK.
You can then find KJ which represents the speed of the wind.
Mt3