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When you are standstill holding a flag, the flag flutters in the direction of wind. When you start running the direction of fluttering of the flag changes to the direction of the wind relative to you. In all case a flag flutters in the direction of the wind relative to the flag.
When you are standstill holding a flag the flag flutters in the north and when you run at 8 m/s due cast. theflag flutters in direction `37^(@)` north of west. Find the wind velocity.

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To solve the problem, we will analyze the situation step by step, using vector components for the velocities involved. ### Step 1: Understand the initial conditions When you are standing still, the flag flutters in the direction of the wind, which is given as north. This means that the wind velocity \( V_w \) has only a northward component: \[ V_w = (0, V_{wn}) \quad \text{(where \( V_{wn} \) is the northward wind velocity)} \] ### Step 2: Analyze the running scenario When you start running at a speed of 8 m/s due east, the flag flutters at an angle of 37 degrees north of west. This means that the resultant velocity of the flag (which is the wind velocity relative to you) can be represented as: \[ V_f = (V_{fx}, V_{fy}) \] where \( V_{fx} \) is the westward component and \( V_{fy} \) is the northward component. ### Step 3: Set up the components of the flag's velocity Since you are running east at 8 m/s, the wind's effect on the flag can be expressed as: \[ V_f = V_w - (8, 0) \] This means that the wind's velocity must be adjusted by subtracting your running velocity. ### Step 4: Resolve the flag's fluttering direction The angle of 37 degrees north of west means we can resolve the components of \( V_f \): - The angle from the west means that the x-component (westward) is negative and the y-component (northward) is positive. - Using trigonometry: \[ \tan(37^\circ) = \frac{V_{fy}}{-V_{fx}} \] From the problem, we know: \[ \tan(37^\circ) = \frac{3}{4} \] Let \( V_{fx} = -x \) (since it is westward) and \( V_{fy} = y \) (since it is northward). Then: \[ \frac{y}{x} = \frac{3}{4} \implies y = \frac{3}{4}x \] ### Step 5: Relate the components to the wind velocity From the previous step, we have: \[ V_f = (V_{fx}, V_{fy}) = (-x, \frac{3}{4}x) \] Substituting into the equation from Step 3: \[ (-x, \frac{3}{4}x) = (0, V_{wn}) - (8, 0) \] This gives us two equations: 1. \( -x = -8 \) (from the x-components) 2. \( \frac{3}{4}x = V_{wn} \) (from the y-components) ### Step 6: Solve for \( x \) and \( V_{wn} \) From the first equation: \[ x = 8 \] Substituting \( x \) into the second equation: \[ V_{wn} = \frac{3}{4}(8) = 6 \text{ m/s} \] ### Conclusion The wind velocity is: \[ \text{Wind Velocity } V_w = (0, 6) \text{ m/s} \]
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When you are standstill holding a flag, the flag flutters in the direction of wind. When you start running the direction of fluttering of the flag changes to the direction of the wind relative to you. In all case a flag flutters in the direction of the wind relative to the flag. Winds is blowing uniformly due north everywhere with velocity 12 m/s. A car mounted with a flag starts running towards cast. after 9s from starts the flag flutters in 53^(@) north of west and after 16 s from the start the flag flutters in 37^(@) north of west. (a) Find velocity of the car 9 s after it starts. (b) Find velocity of the car 16 s after it starts. (c) If the car maintains uniform acceleration, find acceleration of the car.

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