Answer:
The Forces of Flight
At any given time, there are four forces acting upon an aircraft.
These forces are lift, weight (or gravity), drag and thrust. Lift is
the key aerodynamic force that keeps objects in the air. It is the
force that opposes weight; thus, lift helps to keep an aircraft in
the air. Weight is the force that works vertically by pulling all
objects, including aircraft, toward the center of the Earth. In order
to fly an aircraft, something (lift) needs to press it in the opposite
direction of gravity. The weight of an object controls how strong
the pressure (lift) will need to be. Lift is that pressure. Drag is a
mechanical force generated by the interaction and contract of a
solid body, such as an airplane, with a fluid (liquid or gas). Finally,
the thrust is the force that is generated by the engines of an
aircraft in order for the aircraft to move forward.
Explanation:
Answer:
First of all the formula is F= uR,( force= static friction× reaction)
mass= 5+25=30
F= 50
R= mg(30×10)=300
u= ?
F=UR
u= F/R
u= 50/300=0.17N
Answer:
When the air pressure in the throat and outside the body is less than the air pressure in the middle ear, barotrauma occurs.
Explanation:
Ear barotrauma is a medical condition that describes discomfort in the ear which is caused by pressure differences in the inner and outer ear drum.
Usually, the air pressure in the middle ear is the same as the air pressure in the throat and outside the body.
When we swallow, the eustachian tube opens up and air flows out of and into the middle ear, this balances the pressure. But if the eustachian tube is blocked, the air pressure in the throat and outer body become different from the air pressure in the middle ear.
We have the equation of motion , where v i the final velocity, u is the initial velocity, a is the acceleration and s is the displacement
Here final velocity, v = 40m/s
Initial velocity, u = 0 m/s
Displacement s = 2 m
Substituting
So the baseball pitcher accelerates at 400m/ to release a ball at 40 m/s.