JEE Advanced 2022 · Paper 1 · Physics Q8

← JEE Advanced 2022 · Paper 1

PhysicsNumerical+3Question 26 of 54

A projectile is fired from horizontal ground with speed $v$ and projection angle $\theta$ . When the acceleration due to gravity is $g$ , the range of the projectile is $d$ . If at the highest point in its trajectory, the projectile enters a different region where the effective acceleration due to gravity is $g' = \dfrac{g}{0.81}$ , then the new range is $d' = nd$ . The value of $n$ is _____.

Your answer

Answer and worked solution

Official answer: 0.93

First half. Up to the highest point the projectile covers $\frac d2$ horizontally.

Second half. From the top it falls a height $H$ from rest vertically. The fall time is $\sqrt{2H/g'}$ , which is $\sqrt{0.81}=0.9$ of the original fall time, so it covers $0.9\cdot\frac d2$ .

$d'=\frac d2+0.45d=0.95d\implies n=0.95.$

Topics:Projectile motion

← Previous question Next question →

JEE Advanced 2022 · Paper 1, Physics question 8