NOTE: Make sure you draw a free body diagram for these questions, and WRITE OUT the Newton's Second Law equation. Base your answer on your equation, and not on your "instinct." The details of "thrust" are not important here, just know that it is an upward force.
When a helicopter hovers (is at a fixed distance above the ground) the upward thrust (reaction force of the air against the rotor blades) is
equal to the helicopter's weight.
greater than the helicopter's weight.
smaller than the helicopter's weight.
zero.
If a helicopter moves straight upward with constant velocity, the net force on it is
zero.
greater than its weight.
smaller than its weight.
equal to its weight.