Which statement BEST explains why Orion is only visible for a few months of the year? A.
As the Moon orbits Earth, it can block the view of stars in the night sky.
B.
As Earth rotates on its axis, the direction that Earth faces at night changes.
C.
As the stars of Orion rotate around Earth, they can be blocked by Earth itself.
D.
As Earth revolves around the Sun, the direction that Earth faces at night changes.

The diagram shows a wave. the quantity shown is the amplitude. this quantity is directly proportional to which of these other quantities? a) energy b) frequency c) period d) wavelength

A55-kg pilot flies a jet trainer in a half vertical loop of 1200-m radius so that the speed of the trainer decreases at a constant rate. knowing that the plane has a speed of 550 km/h at point a, and the pilot experiences weightlessness at point c (i.e., the normal force from the seat bottom is zero), determine (a) the deceleration of the plane, (b) the force exerted on her by the seat of the trainer when the trainer is at point b.

What does the negative sign in f = –kx mean?