Which statement correctly describes the differences between positive and negative acceleration? a) Positive acceleration describes a change in speed; negative acceleration describes no change in speed.

b) Positive acceleration describes no change in speed; negative acceleration describes a change in speed.

c) Positive acceleration describes an increase in speed; negative acceleration describes a decrease in speed.

d) Positive acceleration describes a decrease in speed; negative acceleration describes an increase in speed.

You and a friend (alex) are at a a tree-top adventure park .. . part of the course requires you to climb up a rope. you both climb the same rope in the same amount of time. however, the tension in the rope is greater when alex climbs. who did the most work? alex did - more tension means more force - more force means more work was done you did - less tension means less force - less force means more work was done to find the work done, the force exerted and distance moved are multiplied. a couch is moved twice before you are happy with its placement. the same force was used to move the couch both times. if more work is done the first time it is moved, what do you know about the distance it was moved? when more work was done, the couch was moved less. when more work was done, the couch was moved further. when more work was done, the couch wasn't moved at all. when more work was done, the couch was moved the same distance.

Could we see a galaxy that is 20 billion light-years away?

Which of the following forces require physical contact? tension air resistance friction magnetic force applied force