motion and force

Who observed that in the absence of friction, an object in horizontal motion continues to move at the same speed with no additional force?

• Einstein

• Newton

• Galileo

• Aristotle

Which one of Newton’s Laws of Motion cannot be demonstrated in a typical setting on Earth due to friction and gravity?

• First

• Second

• Third

• All of the above

• None of the above

Bernoulli’s principle states that since the total energy in a closed system varies, if one element in a fluid system is decreased, another must increase to counterbalance it.

• Change “increased” to “decreased”

• Change “varies” to “is constant”

• Change “decreased” to “increased”

• No changes are needed

Which of the following can be done to reduce the effects of shockwaves and sonic booms on supersonic aircraft? (Input all that apply, then push the ENTER button.)

• decrease thickness of wings

• decrease the length of the nose

• increase wingspan

• sweep wings back

Slight increases in the angle of attack of an airfoil (wing) will normally cause

• an increase in speed due to the faster airflow over the top surface

• an increase in drag thus slowing the aircraft to the point of losing lift

• a decrease in lift due to the longer path of airflow over the wing

• an increase in lift due to the longer path of airflow over the wing

The vector sum of all the forces acting on an object; also called resultant force

• Net force

• Joules

• Shock wave

• Sonic boom

The condition of unrestrained motion in a gravitational field

• G force

• Free fall

• Gravity

• Energy

That component of the total aerodynamic force exerted by the air on an airfoil, having a direction opposite to the force of gravity, enabling an aircraft to stay aloft.

• Lift

• Push

• Drag

• Thrust

A disturbance that occurs when an object reaches the speed of sound or greater, and pressure waves in front of and behind the object are forced together and compressed.

• Sonic boom

• Sonic wave

• Shock wave

• Doppler effect

Change in velocity per unit of time is called what?

• The theory of relativity

• Newtonian motion

• Acceleration

• Aerodynamics