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A man is sitting on the shore of a river...

A man is sitting on the shore of a river. He is in the line of a 1.0 m long boat and is 5.5 m away from the centre of the boat. He sishes to throw an apple into the boat. If he can throuw the apple only wihta speed of 10 m/s, find the minimum and maximum angles of projection for successful shot. Assume that the point of projection and the edge of the boat are in the same horizontal level

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To solve the problem of determining the minimum and maximum angles of projection for the man to successfully throw an apple into the boat, we can follow these steps: ### Step 1: Understand the Problem The man is 5.5 m away from the center of the boat, which is 1 m long. Therefore, the distance from the man to the nearest edge of the boat is \(5.5 - 0.5 = 5.0\) m, and the distance to the far edge of the boat is \(5.5 + 0.5 = 6.0\) m. ### Step 2: Use the Range Formula The range \(R\) of a projectile is given by the formula: \[ R = \frac{u^2 \sin 2\theta}{g} \] where: - \(u\) = initial velocity (10 m/s) - \(g\) = acceleration due to gravity (approximately \(10 \, \text{m/s}^2\)) - \(\theta\) = angle of projection ### Step 3: Calculate for the Minimum Distance (5.0 m) To find the angle for the minimum distance (5.0 m): \[ 5.0 = \frac{(10)^2 \sin 2\theta_1}{10} \] This simplifies to: \[ 5.0 = 10 \sin 2\theta_1 \] \[ \sin 2\theta_1 = 0.5 \] From this, we can find \(2\theta_1\): \[ 2\theta_1 = 30^\circ \quad \text{or} \quad 2\theta_1 = 150^\circ \] Thus, the possible angles are: \[ \theta_1 = 15^\circ \quad \text{or} \quad \theta_1 = 75^\circ \] ### Step 4: Calculate for the Maximum Distance (6.0 m) Now, for the maximum distance (6.0 m): \[ 6.0 = \frac{(10)^2 \sin 2\theta_2}{10} \] This simplifies to: \[ 6.0 = 10 \sin 2\theta_2 \] \[ \sin 2\theta_2 = 0.6 \] From this, we can find \(2\theta_2\): \[ 2\theta_2 = \arcsin(0.6) \quad \text{or} \quad 2\theta_2 = 180^\circ - \arcsin(0.6) \] Calculating \(\arcsin(0.6)\): \[ 2\theta_2 \approx 36.87^\circ \quad \text{or} \quad 2\theta_2 \approx 143.13^\circ \] Thus, the possible angles are: \[ \theta_2 \approx 18.43^\circ \quad \text{or} \quad \theta_2 \approx 71.57^\circ \] ### Step 5: Conclusion The minimum angle of projection is \(15^\circ\) and the maximum angle of projection is \(75^\circ\). ### Final Answer - Minimum angle: \(15^\circ\) - Maximum angle: \(75^\circ\)

To solve the problem of determining the minimum and maximum angles of projection for the man to successfully throw an apple into the boat, we can follow these steps: ### Step 1: Understand the Problem The man is 5.5 m away from the center of the boat, which is 1 m long. Therefore, the distance from the man to the nearest edge of the boat is \(5.5 - 0.5 = 5.0\) m, and the distance to the far edge of the boat is \(5.5 + 0.5 = 6.0\) m. ### Step 2: Use the Range Formula The range \(R\) of a projectile is given by the formula: \[ ...
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