A truck is moving north at a speed of 70 km/h. The exhause pipe above the truck cab seeds out a tail of smoke that makes an angle of 20 degree east of south behind the truck. If the wind is flowing directly towards the east. What is the speed at that location?

3 answers

Solutions. Showing all the working
70 sin20° = 23.9 km/hr
Think about it. If there were no wind, the smoke would go straight back, appearing to go south

If the wind were blowing at 70 km/hr east, the smoke would go as far east as it did south, making a 45° angle.

So, the more it appears to go to the south, the slower the wind is blowing to the east.
i dont think your is correct because if you assume the angle is 45 in this case the you do 70sin45 it does not give 70km/h

i think the more correct one is using a tan because 70tan45 gives you 70km/h