Rain falls vertically downward at 30 m/s. A car starts from rest and accelerates horizontally at 5 m/s². At what time will the rain strike its vertical windshield at 45° to the horizontal normal?
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Question

Rain falls vertically downward at 30 m/s. A car starts from rest and accelerates horizontally at 5 m/s². At what time will the rain strike its vertical windshield at 45° to the horizontal normal?

G1 Physics · Accepted Answer

At time t, car speed is 5t. Relative rain has horizontal component 5t and vertical component 30. For an angle 45° with the horizontal normal, the two component magnitudes must be equal: 5t = 30. Hence t = 6 s. Option C is correct.