A body is projected vertically upward at t=0 with speed 98 m s⁻¹. Another body is projected upward from the same point with the same speed after 4 s. They meet after:
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Question

A body is projected vertically upward at t=0 with speed 98 m s⁻¹. Another body is projected upward from the same point with the same speed after 4 s. They meet after:

G1 Physics · Accepted Answer

Let t be time from the first launch. First body: y₁=98t-4.9t². Second: y₂=98(t-4)-4.9(t-4)². Set y₁=y₂. The t² terms cancel, giving t=12 s. Option D.