Weight and Thrust

How is thrust produced in a drone?

• As the propellers rotate, air pushes up through the drone’s center of gravity

• The battery sends a signal to make the drone move up.

• Gravity pulls the drone down and the drone pushes back up.

• As the propellers rotate, they push air down and the air pushes back on the propellers.

The amount of thrust generated by a propeller depends upon _____.

• Its size, shape and speed of rotation

• Its shape and pitch

• Its thrust constant and length

• Its speed and composition

As rotational speed increases, thrust ​ (a)  

• increases exponentially
• increases at the same rate
• decreases exponentially
• decreases at the same rate

What do you know about a 7050 propeller?

• It has a pitch of 7 inches and is 5 inches long.

• It is 7 inches long and has a 5 inch pitch.

• It is capable of rotating at 7050 RPS.

• It will produce a thrust of 70.5 N at maximum speed.

Drag force is directly proportional to ____.

• thrust

• shorter and faster blades

• velocity

• longer and slower blades

The mathematical equation for torque is k_{t x} ​ ​ (a)  

• w2
• gravity
• mass
• force

What limits the maximum amount of torque a motor can produce?

• The no load speed

• The stall torque

• The amount of current used to turn the motor

• The type of controller used to operate the motors

What does the maximum operating point of a given propeller and motor combination reveal?

• How a motor will perform with a particular propeller.

• Where the motor and propeller torque curves intersect

• The x coordinate is the maximum operating speed.and the y coordinate is the maximum operating torque.

• All of the answers are correct

How can thrust be increased?

• Decrease payload occlusion

• Choose a motor with a higher KV rating

• All answers are correct

• Choose a battery with a higher voltage

Why is the thrust-to-weight ratio (T/W) important to consider when designing your drone?

• The opposing forces of thrust and weight must always be balanced.

• Total thrust must exceed total weight in order to maneuver the drone.

• Thrust always pulls the drone upward and weight is a force that pulls the drone downward.

• It’s not; the thrust-to-drag ratio is more important.