Chapter 6: Q18 CQ (page 220)
A non-rotating frame of reference placed at the centre of the Sun is very nearly an inertial one. Why is it not exactly an inertial frame?
The non-rotating frame will also wobble a bit and hence would not be completely inertial.
Over 30 million students worldwide already upgrade their learning with Vaia!
All the tools & learning materials you need for study success - in one app.
Get started for free
Astronomical observations of our Milky Way galaxy indicate that it has a mass of about solar masses. A star orbiting on the galaxy’s periphery is about light-years from its center.
(a) What should the orbital period of that star be?
(b) If its period is instead, what is the mass of the galaxy? Such calculations are used to imply the existence of “dark matter” in the universe and have indicated, for example, the existence of very massive black holes at the centers of some galaxies.
Suppose a mass is moving in a circular path on a frictionless table as shown in figure. In the Earth’s frame of reference, there is no centrifugal force pulling the mass away from the centre of rotation, yet there is a very real force stretching the string attaching the mass to the nail. Using concepts related to centripetal force and Newton’s third law, explain what force stretches the string, identifying its physical origin.
A geosynchronous Earth satellite is one that has an orbital period of precisely 1 day. Such orbits are useful for communication and weather observation because the satellite remains above the same point on Earth (provided it orbits in the equatorial plane in the same direction as Earth’s rotation). Calculate the radius of such an orbit based on the data for the moon in Table 6.2.
A baseball pitcher brings his arm forward during a pitch, rotating the forearm about the elbow. If the velocity of the ball in the pitcher’s hand is and the ball is 0.300 m from the elbow joint, what is the angular velocity of the forearm?
What is the ideal banking angle for a gentle turn of \(1.20{\rm{ km}}\) radius on a highway with a \(105{\rm{ km}}/{\rm{h}}\) speed limit (about \(65{\rm{ mi}}/{\rm{h}}\)), assuming everyone travels at the limit?
What do you think about this solution?
We value your feedback to improve our textbook solutions.
