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Projectile Motion Physics Motion in Plane Physics Class 11th

Two projectiles thrown at $30 ° a n d 45 °$ with the horizontal respectively, reach the maximum height in same time. The ratio of their initial velocities is

Option 1 -

$1 : \sqrt[]{2}$

Option 2 -

2 : 1

Option 3 -

$\sqrt[]{2} : 1$

Option 4 -

1 : 2

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Asked by Shiksha User

1 Answer

Answered by

Payal Gupta | Contributor-Level 10

a month ago

Correct Option - 3

Detailed Solution:

H₁ = H₂

$\frac{u_{1}^{2} s i n^{2} θ_{1}}{2 g} = \frac{u_{2}^{2} s i n^{2} θ_{2}}{2 g}$

$\Rightarrow u_{1}^{2} {(s i n 30 °)}^{2} = {u_{2}}^{2} {(s i n 45 °)}^{2}$

$\Rightarrow$ $\frac{u_{1}}{u_{2}}$ $=2$

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Draw velocity diagram of A w.r.t. B

If A hits B

Then Relative velocity perpendicular to the line joining A to B will be zero.

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Two projectiles thrown at $30 ° a n d 45 °$ with the horizontal respectively, reach the maximum height in same time. The ratio of their initial velocities is