Concept explainers
Comet Wild 2 In 2004, a NASA spacecraft named Stardust flew within 147 miles of Comet Wild 2 (pronounced “Vilt 2”), zooming by it at 6200 m/s, about six times the speed of a rifle bullet. Photos taken by Stardust show that the comet is roughly spherical, as shown in Figure 12, with a radius of 2.7 km. It has also been determined that the acceleration due to gravity on the surface of Wild 2 is 0.00010g. What is the minimum speed needed for an object to escape from the surface of Wild 2?
Figure 12-40 Comet Wild 2 and some of its surface features, including the Walker basin, the site of unusual jets of outward-flowing dust and rocks. (Problem 79)
Want to see the full answer?
Check out a sample textbook solutionChapter 12 Solutions
Physics (5th Edition)
Additional Science Textbook Solutions
College Physics
Physics: Principles with Applications
The Cosmic Perspective Fundamentals (2nd Edition)
Life in the Universe (4th Edition)
University Physics with Modern Physics (14th Edition)
Sears And Zemansky's University Physics With Modern Physics
- Model the Moons orbit around the Earth as an ellipse with the Earth at one focus. The Moons farthest distance (apogee) from the center of the Earth is rA = 4.05 108 m, and its closest distance (perigee) is rP = 3.63 108 m. a. Calculate the semimajor axis of the Moons orbit. b. How far is the Earth from the center of the Moons elliptical orbit? c. Use a scale such as 1 cm 108 m to sketch the EarthMoon system at apogee and at perigee and the Moons orbit. (The semiminor axis of the Moons orbit is roughly b = 3.84 108 m.)arrow_forwardIn Example 2.6, we considered a simple model for a rocket launched from the surface of the Earth. A better expression for the rockets position measured from the center of the Earth is given by y(t)=(R3/2+3g2Rt)2/3j where R is the radius of the Earth (6.38 106 m) and g is the constant acceleration of an object in free fall near the Earths surface (9.81 m/s2). a. Derive expressions for vy(t) and ay(t). b. Plot y(t), vy(t), and ay(t). (A spreadsheet program would be helpful.) c. When will the rocket be at y=4R? d. What are vy and ay when y=4R?arrow_forwardAs their booster rockets separate, Space Shuttle astronauts typically feel accelerations up to 3g, where g = 9.80 m/s2. In their training, astronauts ride in a device where they experience such an acceleration as a centripetal acceleration. Specifically, the astronaut is fastened securely at the end of a mechanical arm, which then turns at constant speed in a horizontal circle. Determine the rotation rate, in revolutions per second, required to give an astronaut a centripetal acceleration of 3.00g while in circular motion with radius 9.45 m.arrow_forward
- The Vomit Comet. In microgravity astronaut training and equipment testing, NASA flies a KC135A aircraft along a parabolic flight path. As shown in Figure P3.45, the aircraft climbs from 24 000 ft to 31 000 ft, where it enters a parabolic path with a velocity of 143 m/s nose high at 45.0 and exits with velocity 143 m/s at 45.0 nose low. During this portion of the flight, the aircraft and objects inside its padded cabin are in free fall; astronauts and equipment float freely as if there were no gravity. What are the aircrafts (a) speed and (b) altitude at the top of the maneuver? (c) What is the time interval spent in microgravity?arrow_forwardThe astronaut orbiting the Earth in Figure P3.27 is preparing to dock with a Westar VI satellite. The satellite is in a circular orbit 600 km above the Earth’s surface, where the free-fall acceleration is 8.21 m/s2. Take the radius of the Earth as 6 400 km. Determine the speed of the satellite and the time interval required to complete one orbit around the Earth, which is the period of the satellite. Figure P3.27arrow_forwardMiranda, a satellite of Uranus, is as shown. It can be modeled as a sphere of radius 242 km and mass 6.68 × 1019 kg. (a) Find the free-fall acceleration on its surface. (b) A cliff on Miranda is 5.00 km high. It appears on the limb at the 11 o’clock position as shown and is magnified as shown. If a devotee of extreme sports runs horizontally off the top of the cliff at 8.50 m/s, for what time interval is he in flight? (c) How far from the base of the vertical cliff does he strike the icy surface of Miranda? (d) What will be his vector impact velocity?arrow_forward
- A jet pilot takes his aircraft in a vertical loop , if the jet is moving at a speed of 1140 km/m , at the lowest point of the loop , determine the minimum radius (r) of the circle , so that the centripetal acceleration at the lowest point doesn't exceed 6.4 g's please pay attention , previously you sent the answer , but that was not correct , that's why i am sending againarrow_forwardNASA IS EXPECTED TO SEND A 2600 KG SATELLITE 450 KM ABOVE THE EARTH'S SURFACE. A. WHAT IS ITS RADIUS? B. WHAT SPEED WILL IT HAVE? C. WHAT IS ITS ORBITAL PERIOD? D. WHAT IS ITS RADIAL ACCELERATION?arrow_forwardIn 1993 the spacecraft Galileo sent home an image of asteroid 243 Ida and a tiny orbiting moon (now known as Dactyl), the first confirmed example of an asteroid–moon system. In the image, the moon, which is 1.5 km wide, is 100 km from the center of the asteroid, which is 55 km long. The shape of the moon's orbit is not well known; assume it is circular with a period of 27 h. (a) What is the mass of the asteroid? (b) The volume of the asteroid, measured from the Galileo images, is 14100 km3. What is the density (mass per unit volume) of the asteroid?arrow_forward
- An object moves with a constant speed of 16 m/s around a circle of radius 0.5 m. What is the time period of the motion? What is the magnitude of the centripetal acceleration of the ball? What is the direction of the centripetal acceleration? What is the angle between the circular velocity and acceleration at a given instant of time? How is the circular velocity different from the constant speed of the object moving in a circular path?arrow_forwardTwo planets in circular orbits around a star have speeds of v and 2v. (a) What is the ratio of the orbital radii of the planets? (b) What is the ratio of their periods?arrow_forwardA runner taking part in the 200 m dash must run around the end of a track that has a circular arc with a radius of curvature of 35 m. The runner starts the race at a constant speed. If she completes the 200 m dash in 22.6 s and runs at constant speed throughout the race, what is the magnitude of her centripetal acceleration (in m/s2) as she runs the curved portion of the track?arrow_forward
- Physics for Scientists and Engineers: Foundations...PhysicsISBN:9781133939146Author:Katz, Debora M.Publisher:Cengage LearningPrinciples of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage LearningUniversity Physics Volume 1PhysicsISBN:9781938168277Author:William Moebs, Samuel J. Ling, Jeff SannyPublisher:OpenStax - Rice University