Recent content by Vijay Bhatnagar

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    Projectile motion snowball help

    The choice of the origin is optional. You could take the top point as y=0 or the ground as y=0. In the first case initial displacement will be 0 and final displacement -14m. In the second case initial and final displacements will be +14m and 0 respectively. All equations for y-axis will written...
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    Projectile motion snowball help

    Your equation for x-axis is correct. However, in the equations along y axis, the initial velocity should be with -ve sign (-4.5 m/s) because it is downward (same reason acceleration g is -ve). As the snowball hits the ground, vertical displacement is -14m (note the -ve sign). Put y=-14 in the...
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    How Close to Speaker B Causes Destructive Interference at 172 Hz?

    Take n=1 for shortest distance from speaker B.
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    Calculating Work Done by Gravity on Thrown Ball

    Work done = Force x Displacement. What is gravitational force acting on the ball? What is the displacement (not distance travelled) between the initial position and final positions of the ball?
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    Angle of Queue Ball after elastic collision

    You have written equations for kinetic energy conservation. Write an equation for conservation of momentum also. Then solve.
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    Calculating Power Loss from Voltage Change at 3 Ohms Resistance

    Determine the current flowing at 12000 V and 520 kW. Power wasted I^2R. Next determine the current at 50000 V and 520 kW (it will be much less than earlier). Determine power wasted. Find the difference.
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    What is the equilibrium condition for a double inclined plane?

    What about mgsin(theta) component on each block? Further on one of the blocks the frictional force will be up the incline and on the other down.
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    Momentum: Solving Qs on Man Throwing Rocks in Lake

    Your solution for a) is correct. In solution for b) when the heavier rock is thrown the man is still holding the other rock. So his net weight will be 115 kg. The second rock is thrown with a speed of 20 m/s relative to the man, in the direction opposite to in which the man is moving after...
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    How Do You Calculate Tension and Acceleration in a Rotating Cylinder System?

    In that case what you have done is basically correct except that there are two cords carrying equal weights, hence equal tensions T. Net torque on the cylinder will be 2TR and the relation will be 4T/M = a. Solve this one and mg - T = Ma to get T and a. a will be constant. Is B) finding...
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    How Do You Calculate Tension and Acceleration in a Rotating Cylinder System?

    The cylinder (Mass M) is rotating on a fixed axis and the equal masses are connected at the ends of a rope wrapped around the cylinder. So why should the masses move. If the masses were unequal, the heavier one would move down.
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    Car Collision: Help Solve Velocity Before Impact

    This is basically a kinematics problem rather than a collision one. Let the velocity of car before collision be u. Final velocity is zero. Acceleration (retardation) is 20g = -196 m/s^2 (min) and 25g = -245 m/s^2 (max). Displacement = Dent in the truck + collapse in the car = 105 cm = 1.05 m...
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    Incline plane and static friction

    This angle at which the block just starts to slide is called sliding angle. What is the relation between the tangent of sliding angle and coefficient of static friction?
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