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The following physics responses are provided by a student and, as such, should be considered in that context. While every effort is made for accuracy, absolute correctness cannot be fully guaranteed.
| C | I | Question | Answer |
|---|---|---|---|
| 4 | A 15-kg block rests on a level frictionless surface and is attached by a light string to a 5.0-kg hanging mass where the string passes over a massless frictionless pulley. If g = 9.8 m/s2, what is the tension in the connecting string? | 37N | |
| 5 | A 15.0-kg crate, initially at rest, slides down a ramp 2.0 m long and inclined at an angle of 20° with the horizontal. If there is no friction between ramp surface and crate, what is the kinetic energy of the crate at the bottom of the ramp? (g = 9.8 m/s2) | 100J | |
| 4 | A 150-N sled is pulled up a 28° slope at a constant speed by a force of 100 N. What is the coefficient of kinetic friction between sled and slope? | 0.22 | |
| 5 | A 2 000-kg ore car rolls 50.0 m down a frictionless 10.0° incline. If there is a horizontal spring at the end of the incline, what spring constant is required to stop the ore car in a distance of 1.00 m? | 340 kN/m | |
| 4 | A 2 000-kg sailboat experiences an eastward force of 3 000 N by the ocean tide and a wind force against its sails with magnitude of 6 000 N directed toward the northwest (45° N of W). What is the direction of the resultant acceleration? | 74° N of W | |
| 6 | A 2 500-kg truck moving at 10.00 m/s strikes a car waiting at a traffic light, hooking bumpers. The two continue to move together at 7.00 m/s. What was the mass of the struck car? | 1070 kg | |
| 13 | A 2.0-m long piano string of mass 10 g is under a tension of 338 N. Find the speed with which a wave travels on this string. | 260 m/s | |
| 11 | A 2.0-m2 Thermopane window is constructed, using two layers of glass 4.0 mm thick, separated by an air space of 5.0 mm. If the temperature difference is 20 C° from the inside of the house to the outside air, what is the rate of heat flow through this window? (Thermal conductivity for glass is 0.84 J/s×m×°C and for air 0.023 4 J/s×m×°C.) | 180 W | |
| 12 | A 2.0-mol ideal gas system is maintained at a constant volume of 4.0 L. If 100 J of heat is added, what is the work done on the system? | zero | |
| 5 | A 2.00-kg ball has zero kinetic and potential energy. Ernie drops the ball into a 10.0-m-deep well. Just before the ball hits the bottom, the sum of its kinetic and potential energy is: | zero | |
| 5 | A 2.00-kg ball has zero potential and kinetic energy. Maria drops the ball into a 10.0-m-deep well. After the ball comes to a stop in the mud, the sum of its potential and kinetic energy is: | -196J | |
| 12 | A 2.00-kg block of ice is at STP (0°C, 1 atm) while it melts completely to water. What is its change in entropy? (For ice, Lf = 3.34 ´ 105 J/kg) | 2450 J/K | |
| 11 | A 2.00-kg copper rod is 50.00 cm long at 23°C. If 40000 J are transferred to the rod by heat, what is its change in length? ccopper = 387 J/kg·°C and acopper = 17*10^-6/°C. | 0.044 cm | |
| 10 | A 2.00-L container holds half a mole of an ideal gas at a pressure of 12.5 atm. What is the gas temperature? (R = 0.082 1 L*atm/mol*K) | 609 K | |
| 14 | A 2.50-m-long organ pipe is open at one end and closed at the other. Its fundamental tone has wavelength: | 10.0 m. |