Two projectiles are projected at $30^{\circ}$ and $60^{\circ}$ with the horizontal with the same speed. The ratio of the maximum height attained by the two projectiles respectively is:
Solution
<p>Let the initial speed of both projectiles be v. The maximum height attained by a projectile can be calculated using the formula:</p>
<p>$H = \frac{v^2 \sin^2 \theta}{2g}$</p>
<p>where H is the maximum height, v is the initial speed, θ is the angle of projection, and g is the acceleration due to gravity.</p>
<p>For the projectile projected at 30°, the maximum height is:</p>
<p>$$H_1 = \frac{v^2 \sin^2 30^{\circ}}{2g} = \frac{v^2 \times \frac{1}{4}}{2g} = \frac{v^2}{8g}$$</p>
<p>For the projectile projected at 60°, the maximum height is:</p>
<p>$$H_2 = \frac{v^2 \sin^2 60^{\circ}}{2g} = \frac{v^2 \times \frac{3}{4}}{2g} = \frac{3v^2}{8g}$$</p>
<p>Now, let's find the ratio of the maximum heights:</p>
<p>$\frac{H_1}{H_2} = \frac{\frac{v^2}{8g}}{\frac{3v^2}{8g}} = \frac{v^2}{3v^2}$</p>
<p>The v² terms cancel out, and we get:</p>
<p>$\frac{H_1}{H_2} = \frac{1}{3}$</p>
<p>Therefore, the ratio of the maximum heights attained by the two projectiles is 1 : 3</p>
About this question
Subject: Physics · Chapter: Kinematics · Topic: Motion in a Straight Line
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