In 1965, a group of students wore black arm bands to school in protest of American policies in Vietnam. Administrators banned the wearing of armbands on school grounds; however, the students wore them again and were suspended. A lawsuit followed, and the case was eventually taken to the Supreme Court.

Phase changes are chemical changes. true or false

True or false: the cycle of seasons on the earth is caused by the tilt of the earth on its axis toward and away from the sun.

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.