Recent content by Ch3m_

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    Electric field strength at a point between charges

    Homework Statement A +1.0 μC charge is placed at point X. A +4.0 μC charge is placed at point Y, 50 cm from X. How far from X, on the line XY, is the point where the electric field strength is zero? Homework Equations E = Q/4πε0r2 The Attempt at a Solution I know that the electric field is...
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    Periodic Time Calculation for Simple Harmonic Motion with a Spring

    Homework Statement A 0.61 kg mass attached to a spring (k = 27 N m-1) is performing SHM on a smooth horizontal surface. Calculate the periodic time of these oscillations. Homework Equations ω=2π/T ω=2πƒ The Attempt at a Solution I think I need to find out the angular frequency ω of the...
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    Calculating Forces and Angles in a Model Plane System

    Thanks! :)
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    Calculating Forces and Angles in a Model Plane System

    Homework Statement A motorised model plane is attached to a light string anchored to a ceiling. The plane follows a circular path of radius 0∙35 m as shown in Figure 2. The plane has a mass of 0∙20 kg and moves with a constant angular velocity of 6∙0 rad s−1 . (a) Calculate the central force...
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    Finding the overall uncertainty

    Yeah those are the actual uncertainties in the values h = ±0.57% is the % uncertainty, where h is a measurement of length in m To get the uncertainty in h2 you multiply the %uncertainty of h by 2 yeah?
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    Finding the overall uncertainty

    Homework Statement How do I find the overall uncertainty of R when R = (h2+l2)/2h Homework Equations uncertainty in h = ±0.57% uncertainty in h2=±1.14% uncertainty in l2=±7% The Attempt at a Solution √1.142+72+0.572
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    Rotational Motion - Centripetal force

    Thanks, that must mean the normal force = 0 when the car is on the point of losing contact yeah?
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    Rotational Motion - Centripetal force

    Wait so is it v2=gr?
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    Rotational Motion - Centripetal force

    You have the normal force acting upwards, the cars weight acting downwards and the centripetal force acting downwards? a = v2/r ? Weight + centripetal force so mg + (mv2)/r ?
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    Rotational Motion - Centripetal force

    It must be greater than the weight of the car = mg? I don't know how to get an exact value though
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    Rotational Motion - Centripetal force

    The reaction force..? I still don't get it :(
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    Rotational Motion - Centripetal force

    Homework Statement A hump backed bridge is in the form of a circular arc of radius 35m. What is the greatest speed with which a car can cross the bridge without leaving the ground at its highest point? Homework Equations F = m v2/r = mrω2 The Attempt at a Solution I've tried using the equation...