Recent content by new^2^physics

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    Acceleration is (-2.0i + 4.0j), velocity is 12 m/s

    Okay, so I am going to play with these equations and try to get closer... a = dv/dt (-2.0i + 4.0j)= 12i / dt dt = 12i / -6.0i + 4.0j dt = -6.0i - 4.0 j v = dr/dt 12 i = xi - 18j / -6.0i - 4.0j 12i(-6.0i - 4.0 j) = xi - 18j oh dear, now I am stuck again and I am not even sure I have done this...
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    Acceleration is (-2.0i + 4.0j), velocity is 12 m/s

    Homework Statement At T=0 a particle leaves the origin with a velocity of 12 m/s in the positive x direction and moves in the xy plane with a constant acceleration of (-2.0i + 4.0j)m/s^2. At the instant the y coordinate of the particle is 18 m, what is the x coordinate of the particle...
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    Why Does the Sign of Acceleration Affect My Physics Calculation?

    I am sorry DH, I will change the way I post... Its just that I have shed a million tears from physics, and I am getting frusterated. I apologize for not posting in normal English
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    Why Does the Sign of Acceleration Affect My Physics Calculation?

    Okay, so just to make sure I 100% understand... in this question the initial vertical velocity is downward thus the acceleration must have the same sign. BUT... If this question was a hint different, and rather than throwing the ball from an upper story window down, it started from the...
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    Why Does the Sign of Acceleration Affect My Physics Calculation?

    Homework Statement A ball is tossed from an upper story window of a building. The ball is given an initial velocity of 8.00 m/s at an angle of 20.0o below the horizon. It strikest he ground at 3.00s later. Calculate the height from which the ball was released. The Attempt at a...
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    2 dimensional motion - calculate particles position

    Homework Statement A particle starts from rest x=0 and moves for 10 s with an acceleration component of +2.0 cm/s2. for the next 20 s, the acceleration component of the particle is -1.0 cm/s2. What is the position of the particle at the end of this motion? Possible answers: a. zero...
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    2 dimensional motion - calculate magnitude of acceleration

    Homework Statement an automobile manufacturer claims that its product will, starting from rest, travel 0.40 km in 9.0s. What is the magnitude of the constant acceleration required to do this? 2. The attempt at a solution Vi = 0 m/s t = 9.0 s xi = 0 m xf = 400 m xf- xi = Vit +...
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    Products of rations to convert meters per second to miles per hour

    Homework Statement Which of the following products of ratios gives the conversion factors to convert meters per second (m/s) to miles per hour (mi/hr) Homework Equations a. [5280f/mi] x [12 in/f] x [2.54 cm/1 in] x [100 cm/1m] x [3600 s/1h] b. [5280f/mi] x [12 in/f] x [1 in/ 2.54 cm]...
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    Which one of the quantities below has dimensions equal to ML/T^2?

    Homework Statement Which one of the quantities below has dimensions equal to [ML/T2]? Homework Equations a. mv b. mv2 c. mv2/r d. mvr e. mv2/r2 The Attempt at a Solution I know that ML/T2 is for calculating force for circular motion (I believe) Therefore after breaking it...
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    Zero position in Potential Energy

    Hello Physics Friends, Q: A 23 kg car runs straight off the side of a cliff and plummets into the water which is located 10.0m below. If the car was moving at 12 m/s the instant it left the cliff, determine the following: I understand how to calculate the answer to this...
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    How Is Mechanical Energy Calculated in Thrown Objects?

    1. Homework Statement A 0.50 kg rubber ball is thrown into the air. At a height of 20 m above the ground, it is traveling at 15 m/s. a. what is the balls kinetic energy b. What is its gravitational potential energy relative to the ground? c. how much work was done by someone at ground level...
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    How Do You Calculate Mechanical Energy and Work for a Thrown Ball?

    Please help... with Mechanical Energy Question Homework Statement A 0.50 kg rubber ball is thrown into the air. At a height of 20 m above the ground, it is traveling at 15 m/s. a. what is the balls kinetic energy b. What is its gravitational potential energy relative to the ground? c...
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    Determine the change in internal energy, of the gas during this process

    Homework Statement A gas sample heated in a cylinder used 650 kJ of heat. A piston that compresses the gas does 800 kJ of work. What is the change in internal energy, ΔE, of the gas during this process Homework Equations ΔE = q + w The Attempt at a Solution ΔE = q + w ΔE =...
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