Which statement describes the helicopter's motion?
The helicopter has a constant velocity. The helicopter is accelerating.
A rescue helicopter is moving directly upward at a constant speed.
An object's velocity describes its speed and its direction.
An object has a constant velocity when neither its speed nor its direction is changing. So, an object has a constant velocity when the object is:
moving in a straight line at a constant speed, or
remaining motionless.
If an object does not have a constant velocity, the object is accelerating. An object is accelerating when either its speed or its direction is changing. So, an object is accelerating when the object is:
speeding up,
slowing down, or
changing direction.
The helicopter is moving in a straight line at a constant speed. So, the helicopter has a constant velocity.