Câu hỏi 4: Tìm phương trình chuyển động x y z , ,
trên ba trục toạ độ Descartes của chất
điểm, biết véctơ vị trí của chất điểm có dạng:
a)
2
r i t j t k t       (2 1) ( 2) (2 2)
b)
2 2 r i t j t t kt      (2 ) ( 2 3)
c)
r i t j k    sin (cos t-2t) 3
d)
 
2
r k t j i t t

The graph represents the distance a car travels over time while on the highway. which statement about the car's trip is accurate? a) the car does not move over time. b) the car travels at a constant velocity. c) the car's velocity increases constantly over time. d) the car's velocity decreases constantly over time.

Sodium chloride, nacl, is formed when a sodium atom transfers its electron to a chlorine atom. the difference in charge between the two atoms creates a(n) attraction that bonds them together.

Amoving company collects data about couches they move and displays the data in a table. the force along the ramp, the angle of the ramp, and the height the couch is raised to are shown. which statements correctly compare the work done to move the couches? check all that apply. the same amount of work is done for couches 1 and 3. the same amount of work is done for couches 2 and 3. the work for couch 1 is greater than the work for couch 2. the work for couch 2 is less than the work for couch 3. the work for couch 3 is greater than the work for couch 1. the work for couch 2 is greater than the work for couch 1.