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Kinematics

JEE Main level, single correct, medium

261 of 308

Question 261 of 308

A shell is fired from a fixed artillery gun with an initial speed u such that it hits the target on the ground at a distance $R$ from it. If ${t}_{1}$ and ${t}_{2}$ are the values of the time taken by it to hit the target in two possible ways, the product ${t}_{1}{t}_{2}$ is:

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Answer: (C) $2R/g$

We know for complementary angle range is same for same projection speed.

{t}_{1}=\dfrac{2usin(\theta )}{g}

….. (i)

{t}_{2}=\dfrac{2usin(90-\theta )}{g}

….. (ii)

R=\dfrac{2{u}^{2}sin\theta cos\theta }{g}

.… (iii)
From equation (i) and (ii)

{t}_{1}{t}_{2}=\dfrac{4 {U}^{2}sin\theta cos\theta }{{g}^{2}}

(Using the value of R from equation iii)

{t}_{1}{t}_{2}=\dfrac{2R}{g}

JEE Main question paper PDF

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JEE Main 2025 Apr 2 Shift 1 question paper

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JEE Main Physics practice question on Kinematics (Projectile motion), with the answer and a step-by-step solution. Scan a question from your own book or paper to get a whiteboard video.

A shell is fired from a fixed artillery gun with an initial speed u such that it hits the target on the ground at a distance RRR from it. If t1{t}_{1}t1​ and t2{t}_{2}t2​ are the values of the time taken by it to hit the target in two possible ways, the product t1t2{t}_{1}{t}_{2}t1​t2​ is:

JEE Main question paper PDF

More Physics practice

A shell is fired from a fixed artillery gun with an initial speed u such that it hits the target on the ground at a distance $R$ from it. If ${t}_{1}$ and ${t}_{2}$ are the values of the time taken by it to hit the target in two possible ways, the product ${t}_{1}{t}_{2}$ is: