Recent content by elcaptain

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    Second Law of Thermodynamics - heat pumps and air conditioners

    anything?
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    Second Law of Thermodynamics - heat pumps and air conditioners

    Homework Statement A heat pump operates as an air conditioner, drawing 20000 Btu per hr from a building. It is operating between 21 degrees Celsius and 41 degrees Celsius. a) If the COP (coefficient of performance) is 35% that of a Carnot air conditioner, what is the value of the effective...
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    Solving the Physics of a Curling Stalemate

    worst.help.ever.
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    What is the tangential acceleration?

    i understand there are forces, including centripetal force and gravitational force. but i do not understand how they directly relate to tangential acceleration.
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    What is the tangential acceleration?

    Homework Statement a ball of 2.5kg revolves in a circle on a string with a radius of 0.9m. at the moment when the string makes an angle of 60 degrees below the horizontal, the ball's speed is 7m/s. at this specific point, what is the tangential acceleration?Homework Equations A_t = r*angular...