Two astronauts are floating in space far away from any planets or stars. What is the direction of the gravitational force that they experience, if any? A. They do not experience a gravitational force because there is no large object nearby.
B. Away from each other because they are pulled by distant planets and stars.
C. They experience a gravitational force, but its direction cannot be determined.
D. Toward each other, because there is a gravitational force between them.

Aparticle of mass m is projected with an initial velocity v0 in a direction making an angle α with the horizontal level ground as shown in the figure. the motion of the particle occurs under a uniform gravitational field g pointing downward. (a) write down the lagrangian of the system by using the cartesian coordinates (x, y). (b) is there any cyclic coordinate(s). if so, interpret it (them) physically. (c) find the euler-lagrange equations. find at least one constant of motion. (d) solve the differential equation in part (c) and obtain x and y coordinates of the projectile as a function of time. (e) construct the hamiltonian of the system, h, and write down the hamilton’s equations (canonical equations) of motion.

The diagram shows a series of volcanic island and a hot spot determine the direction of movement of the tectonic plate that for the island

Which pair of quantities includes one quantity that increases as the other decreases during simple harmonic motion?