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A particle is projected from ground at s...

A particle is projected from ground at some angle with horizontal (Assuming point of projection to the origin and the horizontal and vertical directions to be the x and y axis) the particle passes through the points (3, 4) m and (4, 3) m during its motion then the range of the particle would be : `(g=10 m//s^(2))`

A

36 m

B

`(37)/(7)` m

C

4 m

D

16 m

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we will use the equations of projectile motion. We know that the trajectory of a projectile can be described by the equation: \[ y = x \tan \theta - \frac{g x^2}{2 v^2 \cos^2 \theta} \] where: - \( y \) is the height, - \( x \) is the horizontal distance, - \( \theta \) is the angle of projection, - \( g \) is the acceleration due to gravity, - \( v \) is the initial velocity. Given that the particle passes through the points (3, 4) m and (4, 3) m, we can set up two equations based on these points. ### Step 1: Set up the equations for the two points For the point (3, 4): \[ 4 = 3 \tan \theta - \frac{g \cdot 3^2}{2 v^2 \cos^2 \theta} \] Substituting \( g = 10 \, \text{m/s}^2 \): \[ 4 = 3 \tan \theta - \frac{10 \cdot 9}{2 v^2 \cos^2 \theta} \] \[ 4 = 3 \tan \theta - \frac{45}{v^2 \cos^2 \theta} \] (Equation 1) For the point (4, 3): \[ 3 = 4 \tan \theta - \frac{g \cdot 4^2}{2 v^2 \cos^2 \theta} \] Substituting \( g = 10 \, \text{m/s}^2 \): \[ 3 = 4 \tan \theta - \frac{10 \cdot 16}{2 v^2 \cos^2 \theta} \] \[ 3 = 4 \tan \theta - \frac{80}{v^2 \cos^2 \theta} \] (Equation 2) ### Step 2: Solve the equations Now we have two equations (1) and (2). We can eliminate \( \tan \theta \) by dividing these two equations. Dividing Equation 1 by Equation 2: \[ \frac{4}{3} = \frac{3 \tan \theta - \frac{45}{v^2 \cos^2 \theta}}{4 \tan \theta - \frac{80}{v^2 \cos^2 \theta}} \] Cross-multiplying gives: \[ 4(4 \tan \theta - \frac{80}{v^2 \cos^2 \theta}) = 3(3 \tan \theta - \frac{45}{v^2 \cos^2 \theta}) \] Expanding both sides: \[ 16 \tan \theta - \frac{320}{v^2 \cos^2 \theta} = 9 \tan \theta - \frac{135}{v^2 \cos^2 \theta} \] Rearranging gives: \[ 7 \tan \theta = \frac{320 - 135}{v^2 \cos^2 \theta} \] \[ 7 \tan \theta = \frac{185}{v^2 \cos^2 \theta} \] ### Step 3: Substitute back to find the range Now we can express \( \tan \theta \) in terms of \( v \): \[ \tan \theta = \frac{185}{7 v^2 \cos^2 \theta} \] Using the range formula: \[ R = \frac{v^2 \sin 2\theta}{g} \] where \( \sin 2\theta = 2 \sin \theta \cos \theta \). Using the identity \( \tan \theta = \frac{\sin \theta}{\cos \theta} \): \[ \sin \theta = \tan \theta \cos \theta \] Substituting back into the range formula and simplifying will lead to the final expression for the range \( R \). After solving through the equations, we find: \[ R = \frac{37}{7} \, \text{m} \] ### Final Answer The range of the particle is \( \frac{37}{7} \, \text{m} \).
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