Physics Misc Topic Level: University
The specific heat capacity of ice is about 0.5 cal/g* oC. Supposing that it remains at that value all the way to absolute zero, calculate the number of calories it would take to change a 1-gram ice cube to absolute zero (-273oC) to 1 gram of boiling water. How does this number of calories compare with the number of calories required to change the same gram of 100oC boiling water to 100oC steam?
Physics Misc Topic Level: University
When I2 dissolves in methanol, CH3OH, what type of forces must be overcome within the solid I2 to allow it to dissolve?
Physics Misc Topic Level: University
The isotope Cesium-137 which has a half life of 30 years is a product of nuclear power plants. How long will it take for this isotope to decay to about one-sixteenth its original amount?
Physics Misc Topic Level: University
Magnet A has twice the magnetic field strength of magnet B, and at a certain distance, it pulls on magnet B with a force of 50N. With how much force, then does magnet B pull on magnet A?
Physics Misc Topic Level: University
Rearrange the equation [current = voltage/resistance] to express resistance in terms of current and voltage. Then solve: A certain device in a 120-V circuit has a current rating of 20A. What is the resistance of the device (How many ohms)?
Physics Misc Topic Level: University
Find the voltage change when (a) an electric field does 12 J of work on a 0.0001-C charge, and when (b) the same electric field does 24 J work on a 0.0002-C charge.
Physics Misc Topic Level: University
If 50 grams of hot ware at 80oC is poured into a cavity in a very large block of ice at 0oC, what will be the final temperature of the water in the cavity? How much ice must melt in order to cool the hot water down to this temperature?
Physics Misc Topic Level: University
The heat of vaporization of ethyl alcohol is about 200 cal/g. If 2 kg of it were allowed to vaporize in a refrigerator, how many grams of ice would be formed from 0oC water?
Physics Misc Topic Level: University
The specific heat capacity of ice is about 0.5 cal/g* oC. Supposing that it remains at that value all the way to absolute zero, calculate the number of calories it would take to change a 1-gram ice cube to absolute zero (-273oC) to 1 gram of boiling water. How does this number of calories compare with the number of calories required to change the same gram of 100oC boiling water to 100oC steam?
Physics Misc Topic Level: University
A 10-kg iron ball is dropped onto a pavement from a height of 100 m. If half of the heat generated goes into warming the ball, find the temperature increase of the ball. (In SI units, the specific heat capacity of iron is 450 J/kg*oC.) Why is the answer the same for an iron ball of any mass?
Physics Misc Topic Level: University
Many people mistakenly believe that the astronauts orbiting the earth are above gravity. Calculate the acceleration due to gravity g for space shuttle territory 200 kilometers above the earth s surface. Earth s mass is 6 X 1024kg, and its radius is 6.38 X 106m (6380 km). Your answer is what percentage of 9.8 m/s2?
Physics Current Electricity Level: University
Heating effect of currentNichrome wire is used in some in some radiative heaters. (a) Find the resistance needed if the average power output is to be 1.00 kw utilizing 120Vac. (b) What length of nichrome wire having a cross section area of 5.00 mm^2 is needed if the operating temp is 500 deg C. (c) What power will it draw when first turned on?
Physics Current Electricity Level: University
Heating effect of currentNichrome wire is used in some radiative heaters. (a) Find the resistance needed if the average power output is to be 1.00 kw utilizing 120 VAC. (b) What length of nichrome wire having a cross section area of 5.00mm^2 is needed if the operating temp is 500 deg C. (c) What power will it draw when first turned on ?
Physics Current Electricity Level: University
A resistor made of Nichrome wire is used in an application where its resistance cannot change more than 1.00% from its value at 20.0 deg C. over what temp range can it be used? (nichrome resistivity = 100* 10^-8)
Physics Current Electricity Level: University
Find the voltage drop in an extension card having a 0.0600 OHM resistance and through which 5.00 Amp is flowing. (b) A chepaer cord utilizes a thinner wire and has a resistance of 0.300 ohm what is the voltage drop in it when 5.00 Amp flows