Recent content by Kalvarin

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    Calculating K.E: 0.0136 J Solution

    You need to work out it's rotational kinetic energy. I = m*(r^2) I is the moment of inertia of a point mass rotating about a fixed point. Mass of turntable isn't mentioned so assume it is negligible. E = 0.5*I*(w^2) E is the energy of a rotating system, where w is angular frequency...
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    Calculating Time for an Object to Fall in One Dimension

    Hi Vo will be 2.5 m/s in the direction the balloon is moving. If it wasn't then if you where in a moving car and you threw a ball it would fly to the back of the car at the speed the car is moving.. and that don't happen :)
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    Finding Range of Object Shot at 40° Angle

    To work out the range we need to work out the flight time. So first find the time it takes the ball to reach it's highest point using the y-component of it's velocity. Then calculate how long it takes to hit the floor. The sum of these two times is the flight time.
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    Calculating the potential of a uniformily charged spherical solid

    The electric field is only zero inside a conducting sphere. This is because all the charge migrates to the surface and it acts likes a hollow charged shell. In the question it does not say the sphere is conducting, it says it is uniformly charged. Therefore it must be acting as an insulating...
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    What are the two questions on kinematics?

    I've worked through part one and you will get a complicated looking equation for \Theta. I got: (2(u\hat{}2) +2u)*sin\hat{}2(\Theta) + h*sin(\Theta) - 2u = 0 Where u is the initial velocity. If you replace sin(\Theta) with x you can solve for x just like an ordinary quadratic. Then when...
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    Sum of Forces in x- and y-directions

    Hi The first part is right. For the second part we know that the normal force (R) is equal to m*g when no other forces are acting on the chair. In this case there is an external force acting on the chair, a component of this force is acting in the upwards y direction. Yet there is no...
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    Displacement Calculation for a Moving Cyclist

    You got to get everything in the same units. We have velocity in m/s so we want time in seconds. 1.2 hours = 72 minutes = 4320 seconds Then just use: Distance = Velocity*Time
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    How Does a Rocket Behave After Engine Shutdown?

    You need to calculate the distance the rocket travels after the engine fails before it comes to a complete stop.
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    Boolean algebra conceptual questions

    a b a*b 0 0 0 0 1 0 1 0 0 1 1 1 This is the truth table for the above statement. Don't think of it as an implication. All it is saying is a*b only has a non-zero value when both a and b have values greater than 0.
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    How Do You Calculate Revolutions Per Minute for an Astronaut in a Centrifuge?

    Oh ok, well then just use your value of omega in the formula anden gave you. That is the time for 1 revolution.
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    How Do You Calculate Revolutions Per Minute for an Astronaut in a Centrifuge?

    Well rpm for a gven radius can infinetly many values. How did you work out the value of omega?
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    How Do You Calculate Revolutions Per Minute for an Astronaut in a Centrifuge?

    You need to know more data to work out the rpm, knowing just the radius of the centrifuge is not enough.
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