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Two particles are projected in air with ...

Two particles are projected in air with speed `v_(0)` at angles `theta_(1)` and `theta_(2)` (both acute) to the horizontal,respectively.If the height reached by the first particle greater than that of the second,then thick the right choices

A

Angle of projection `q_(1) gt q_(2)`

B

Time of flight `T_(1) gt T_(2)`

C

Horizontal range `R_(1) gt R_(2)`

D

Total energy `U_(1) gt U_(2)`

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To solve the problem step by step, we need to analyze the motion of the two particles projected at different angles but with the same initial speed. ### Step 1: Understanding the maximum height formula The maximum height \( h \) reached by a projectile is given by the formula: \[ h = \frac{u^2 \sin^2 \theta}{2g} \] where \( u \) is the initial speed, \( \theta \) is the angle of projection, and \( g \) is the acceleration due to gravity. ### Step 2: Setting up the equations for both particles Let: - \( h_1 \) be the height reached by the first particle (angle \( \theta_1 \)) - \( h_2 \) be the height reached by the second particle (angle \( \theta_2 \)) From the formula, we have: \[ h_1 = \frac{v_0^2 \sin^2 \theta_1}{2g} \] \[ h_2 = \frac{v_0^2 \sin^2 \theta_2}{2g} \] ### Step 3: Comparing the heights According to the problem, \( h_1 > h_2 \). Thus: \[ \frac{v_0^2 \sin^2 \theta_1}{2g} > \frac{v_0^2 \sin^2 \theta_2}{2g} \] Since \( v_0 \) and \( g \) are the same for both particles, we can simplify this to: \[ \sin^2 \theta_1 > \sin^2 \theta_2 \] ### Step 4: Analyzing the sine function Since both angles \( \theta_1 \) and \( \theta_2 \) are acute (between 0 and 90 degrees), the sine function is increasing in this interval. Therefore: \[ \sin \theta_1 > \sin \theta_2 \implies \theta_1 > \theta_2 \] This confirms that the angle of projection for the first particle is greater than that of the second. ### Step 5: Time of flight comparison The time of flight \( T \) for a projectile is given by: \[ T = \frac{2u \sin \theta}{g} \] For both particles: \[ T_1 = \frac{2v_0 \sin \theta_1}{g} \] \[ T_2 = \frac{2v_0 \sin \theta_2}{g} \] Since \( v_0 \) and \( g \) are the same, we can compare: \[ T_1 > T_2 \quad \text{(because } \sin \theta_1 > \sin \theta_2\text{)} \] ### Step 6: Horizontal range comparison The horizontal range \( R \) of a projectile is given by: \[ R = \frac{u^2 \sin 2\theta}{g} \] For both particles: \[ R_1 = \frac{v_0^2 \sin 2\theta_1}{g} \] \[ R_2 = \frac{v_0^2 \sin 2\theta_2}{g} \] Since \( v_0 \) and \( g \) are the same, we can compare: \[ R_1 > R_2 \quad \text{(because } 2\theta_1 > 2\theta_2 \text{ implies } \sin 2\theta_1 > \sin 2\theta_2\text{)} \] ### Step 7: Total mechanical energy comparison The total mechanical energy \( E \) of a projectile is given by: \[ E = \text{Potential Energy} + \text{Kinetic Energy} \] Since both particles are projected with the same initial speed \( v_0 \), their total mechanical energy depends on their mass. If \( m_1 \) and \( m_2 \) are the masses of the first and second particles, respectively, we cannot definitively compare their energies without knowing their masses. ### Conclusion From the analysis: 1. \( \theta_1 > \theta_2 \) (Angle of projection) 2. \( T_1 > T_2 \) (Time of flight) 3. \( R_1 > R_2 \) (Horizontal range) 4. Total energy cannot be compared without knowing the masses. Thus, the correct choices are options 1, 2, and 3.

To solve the problem step by step, we need to analyze the motion of the two particles projected at different angles but with the same initial speed. ### Step 1: Understanding the maximum height formula The maximum height \( h \) reached by a projectile is given by the formula: \[ h = \frac{u^2 \sin^2 \theta}{2g} \] where \( u \) is the initial speed, \( \theta \) is the angle of projection, and \( g \) is the acceleration due to gravity. ...
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