Ahorse canters away from its trainer in a straight line, moving 126 m away in 13.0 s. it then turns abruptly and gallops halfway back in 5.0 s .calculate: (a) its average speed? (b) its average velocity for the entire trip, using "away from the trainer" as the positive direction.

The position of a dragonfly that is flying parallel to the ground is given as a function of time by r⃗ =[2.90m+(0.0900m/s2)t2]i^− (0.0150m/s3)t3j^. a: at what value of t does the velocity vector of the insect make an angle of 34.0 degree clockwise from the x-axis? b: at the time calculated in part (a), what is the magnitude of the acceleration vector of the insect? c : at the time calculated in part (a), what is the direction of the acceleration vector of the insect?

What is the speed of an object at a given moment?

What is the role of lenses in microscopy?