According to general relativity, why does Earth orbit the Sun?
A) Earth orbits the Sun because the mysterious force that we call gravity holds Earth in orbit.
B) Earth is following the straightest path possible through spacetime, but this path happens to go around and around the Sun.
C) Earth orbits the Sun because Earth and Sun are connected by a "rope-like" set of invisible, subatomic particles.
D) Earth orbits the Sun because a spacetime diagram shows the Sun to be a bowl-shaped dip in a rubber sheet.
B
You might also like to view...
When light in medium 1 is reflected from the surface of medium 2 with the indices of refraction of the media being n1 and n2 respectively, the reflected light has a phase difference of 180° if
A) n1 > 3 n2. B) n1 = n2. C) n1 < n2. D) n1 > n2. E) n1 > 2 n2.
The "normal" eye has a near point of 25 cm. If a given individual's near point is 73 cm, for what problem will the eye doctor prescribe correction?
a. myopia b. presbyopia c. hyperopia d. astigmatism e. color blindness
Acceleration: A racing car accelerates uniformly from rest along a straight track. This track has markers spaced at equal distances along it from the start, as shown in the figure. The car reaches a speed of 140 km/h as it passes marker 2. 
Where on the track was the car when it was traveling at half this speed, that is at 70 km/h?
A. Before marker 1 B. At marker 1 C. Between marker 1 and marker 2
Two circular loops carry identical currents, but the radius of one loop is twice that of the other. How do the magnetic fields at the centers of the loops compare?
a) In both cases, the magnetic field at the center would be zero tesla. b) The magnetic field at the center of the larger loop is twice that at the center of the smaller loop. c) The magnetic field at the center of the larger loop is the same as that at the center of the smaller loop. d) The magnetic field at the center of the larger loop is one-half that at the center of the smaller loop. e) The magnetic field at the center of the larger loop is one-fourth that at the center of the smaller loop.