Skip to content
dronacharya.ai
← JEE Main 2022 · 28 Jul · Shift 2
PhysicsInteger+4 / -1Question 21 of 90

JEE Main 2022 · 28 Jul · Shift 2, Physics question 21

A ball is thrown vertically upwards with a velocity of 19.6 ms−1^{-1} from the top of a tower. The ball strikes the ground after 6 s. The height from the ground up to which the ball can rise will be (k5)\left(\dfrac k5\right) m. The value of k is ______ (use g = 9.8 m/s2^2)

Answer and worked solution

Official answer: 392

Tower. −h=19.6×6−4.9×36-h=19.6\times6-4.9\times36, so h=58.8h=58.8 m.

Rise above the tower 19.6219.6=19.6\frac{19.6^2}{19.6}=19.6 m, so the top is 78.4 m =3925=\frac{392}5 m.

Answer: 392