Recent content by physicsnerd7

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    Solve Efficiency Problem: Heat Water in 1000 W Electric Kettle

    Okay so then the 600 s answer is right then because the only thing affecting the heating up of the water is the amount of power the kettle has and not what the kettle is made from. And since the kettle is only 63% efficient then only 630W is going towards heating the water.
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    Solve Efficiency Problem: Heat Water in 1000 W Electric Kettle

    Δt = (mwater x cwater x (Tf of water - Ti of water) + miron x ciron x(Tf iron - Ti iron)) / 630 W Is ^ this correct then. I know that energy can't be created or destroyed and that it is only transferred from one form to another.
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    How Do You Calculate the Specific Heat Capacity of an Unknown Substance?

    Homework Statement A copper calorimeter cup with a mass of 0.27 kg contains 0.125 kg of water. At 17°C. If 95g of an unknown substance at 93°C is placed into the cup, the temperature increases to 35°C. Find the specific heat capacity of the unknown substance. Homework Equations Qreleased +...
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    Solve Efficiency Problem: Heat Water in 1000 W Electric Kettle

    Homework Statement Determine the amount of time it will take a 1000 W electric kettle to heat up 1.0 L of water to boiling point if the water starts at 10 °C and the kettle is made from 400 g of iron. The transfer of heat energy from the kettle to the water is 63%.Homework Equations P = W/Δt Q...
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    Can the Magnet and Picture Move on the Fridge?

    oh okay sorry. Ya I get the forces acting on the magnet and the picture but when I tried to solve for acceleration I get a 0 acceleration because it hasn't yet overcome static friction. Would this statement be correct?
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    Can the Magnet and Picture Move on the Fridge?

    So how would I change my FBD then?
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    Can the Magnet and Picture Move on the Fridge?

    Wait so a magnet attracts the object so would the action force would be on the fridge pulling left and the reaction force would be the fridge pulling on the magnet to the right.
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    Can the Magnet and Picture Move on the Fridge?

    It is to the left because I have my picture with the magnet on the right and it is going on the fridge which is to the left.
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    Can the Magnet and Picture Move on the Fridge?

    yes i drew the FBD. i have Fs pointing up, Fn pointing right, Fg pointing down, and Fapplied from the magnet pointing left. Would the acceleration then be 0 N/kg because it stays stationary? he doesn't give us the answer. :(
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    Can the Magnet and Picture Move on the Fridge?

    Trick Question?? Please help! Homework Statement John hangs a picture of his lovely family on the fridge with a magnet. The magnet applies a force of 15 N. If the magnet and the picture have a mass of 500 g. The coefficient of static friction is 0.40 and the coefficient of kinetic friction is...
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