The site from which an airplane takes off is the origin. The x axis points east; the y axis points straight up. The position and velocity vectors of the plane at a later time are given by and . The plane is most likely
A) just touching down.
B) in level flight in the air.
C) ascending.
D) descending.
E) taking off.

Question

The site from which an airplane takes off is the origin. The x axis points east; the y axis points straight up. The position and velocity vectors of the plane at a later time are given by  and  . The plane is most likely
A) just touching down. 
B) in level flight in the air. 
C) ascending. 
D) descending. 
E) taking off.

Quizplus · Accepted Answer

The position vector has a positive y component, indicating that the plane has ascended from the origin. The velocity vector also has a positive y component, indicating that the plane is still ascending. Therefore, the plane is most likely ascending.

The Site from Which an Airplane Takes Off Is the Origin