Which is an example of a social network? A. a group of parent who post information online about trends in child care
B. a group of coworkers who meet up daily in the cafeteria to learn new skills
C. a group of neighbors who help each other farm a community garden
D. All of the above

Students design a model roller-coaster track. they place a rubber ball at the highest point on the track and let it go. the ball rolls along the track pulled only by the force of gravity. eventually, it comes to a stop. which change to the design will result in the ball moving the greatest distance?

Nitrogen (n2) undergoes an internally reversible process from 6 bar, 247°c during which pν1.2 = constant. the initial volume is 0.1 m3 and the work for the process is 121.14 kj. assuming ideal gas behavior, and neglecting kinetic and potential energy effects, determine heat transfer, in kj, and the entropy change, in kj/s. show the process on a t-s diagram.

What is friction? how does it affect the motion of an object?