HomeAstronomyBoring feedGame LevelsLight Bulb LifeMap ArchivePhysics 2010ScreencapsSpeed TestTrek DataVote 2020WallpaperWeather
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 |
|---|---|---|---|
| 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 | |
| 9 | A fluid has a density of 1 040 kg/m^3. If it rises to a height of 1.8 cm in a 1.0-mm diameter capillary tube, what is the surface tension of the liquid? Assume a contact angle of zero. | 0.046 N/m | |
| 7 | A cylindrical space colony 8 km in diameter and 30 km long has been proposed as living quarters for future space explorers. Such a habitat would have cities, land and lakes on the inside surface and air and clouds in the center. All this would be held in place by the rotation of the cylinder about the long axis. How fast would such a cylinder have to rotate to produce a 1-g gravitational field at the walls of the cylinder? | 0.05 rad/s | |
| 7 | A Ferris wheel starts at rest and builds up to a final angular speed of 0.70 rad/s while rotating through an angular displacement of 4.9 rad. What is its average angular acceleration? | 0.05 rad/s^2 | |
| 9 | In order to overcome a surface tension of a fluid, a force of 1.32*10^-2 N is required to lift a wire ring of circumference 12.0 cm. What is the surface tension of the fluid? | 0.055 N/m | |
| 8 | A majorette takes two batons and fastens them together in the middle at right angles to make an "x" shape. Each baton was 0.80 m long and each ball on the end is 0.20 kg. (Ignore the mass of the rods.) What is the moment of inertia if the arrangement is spun around an axis formed by one of the batons? | 0.064 kg*m^2 | |
| 11 | A 0.2-kg aluminum plate, initially at 20°C, slides down a 15-m-long surface, inclined at a 30° angle to the horizontal. The force of kinetic friction exactly balances the component of gravity down the plane so that the plate, once started, glides down at constant velocity. If 90% of the mechanical energy of the system is absorbed by the aluminum, what is its temperature increase at the bottom of the incline? (Specific heat for aluminum is 900 J/kg×°C.) | 0.07 C° | |
| 13 | Suppose a 0.3-kg mass on a spring that has been compressed 0.10 m has elastic potential energy of 1.0 J. How much further must the spring be compressed to triple the elastic potential energy? | 0.07 m | |
| 3 | A ball is rolled horizontally off a table with an initial speed of 0.24 m/s. A stop watch measures the ball's trajectory time from table to the floor to be 0.30 s. How far away from the table does the ball land? (g = 9.8 m/s2 and air resistance is negligible) | 0.072 m | |
| 9 | The bottom of a flat-bottomed aluminum boat has area = 4.0 m2 and mass = 60 kg. If two fishermen and their fishing gear with total mass of 300 kg are placed in the boat, how much lower will the boat ride in the water? (H2O density = 1.0*10^3 kg/m3) | 0.075 m | |
| 13 | The position of a 0.64-kg mass undergoing simple harmonic motion is given by x = (0.160 m) cos (πt/16). What is its position at t = 5.0 s? | 0.089 m | |
| 13 | Equal wavelength waves of amplitude 0.25 m and 0.15 m interfere with one another. What is the resulting minimum amplitude that can result? | 0.10 m | |
| 1 | A cereal box has the dimensions of 0.19 m X 0.28 m X 0.070 m. If there are 3.28 feet per meter, then what is the volume of the box in cubic feet? | 0.13 cubic feet | |
| 8 | A majorette takes two batons and fastens them together in the middle at right angles to make an "x" shape. Each baton was 0.80 m long and each ball on the end is 0.20 kg. (Ignore the mass of the rods.) What is the moment of inertia if the arrangement is spun around an axis through the center perpendicular to both rods? | 0.13 kg*m^2 | |
| 6 | A 20-g bullet moving at 1 000 m/s is fired through a one-kg block of wood emerging at a speed of 100 m/s. What is the kinetic energy of the block that results from the collision if the block had not been moving prior to the collision and was free to move? | 0.16 kJ |