The following diagrams all show the same star, but each shows a different planet orbiting the star. the diagrams are all scaled the same. (for example, you can think of the tick marks along the line that passes through the sun and connects the nearest and farthest points in the orbit as representing distance in astronomical units ( rank the planets from left to right based on their average orbital distance from the star, from longest to shortest. (distances are to scale, but planet and star sizes are not.)

Ablock of mass m = 2.5 kg is attached to a spring with spring constant k = 710 n/m. it is initially at rest on an inclined plane that is at an angle of θ = 23° with respect to the horizontal, and the coefficient of kinetic friction between the block and the plane is μk = 0.19. in the initial position, where the spring is compressed by a distance of d = 0.16 m, the mass is at its lowest position and the spring is compressed the maximum amount. take the initial gravitational energy of the block as zero. a) what is the block's initial mechanical energy? b) if the spring pushes the block up the incline, what distance, l, in meters will the block travel before coming to rest? the spring remains attached to both the block and the fixed wall throughout its motion.

What is the angular momentum of the bar about the axle?

1. jay fills a wagon with sand (about 20 kg) and pulls it with a rope 30 m along the beach. he holds the rope 25° above the horizontal. the rope exerts a 20-n tension force on the wagon. how much work does the rope do on the wagon?