tan=60∘=vvrg ........(1)
tan45∘=(β+1)vvrg ..........(2)
3v=(β+1)v
β=3−1=0.732
When a car is at rest, its driver sees rain drops falling on it vertically. When driving the car with speed v, he sees that rain drops coming at an angle 60∘ from the horizontal. On further increasing the speed of the car to (1+β)v, this angle changes to 45∘. The value of β is close to :
Held on 6 Sept 2020 · Verified 6 Jul 2026.
0.50
0.41
0.37
0.73
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