An 80.0-kg object is falling and experiences a drag force due to air resistance. the magnitude of this drag force depends on its speed, v, and obeys the equation fdrag=(12.0n⋅s/m)v+(4.00n⋅s2/m2)v2. what is the terminal speed of this object?

 Terminal velocity of object = 12.58 m/s

Explanation:

 We know that the terminal velocity is attained when drag force and gravitational force are of the same magnitude.

Gravitational force = mg = 80 * 9.8 = 784 N

Drag force =

Equating both, we have

  So v = 12.58 m/s or v = -15.58 m/s ( not possible)

 So terminal velocity of object = 12.58 m/s    

d. air pressure decreases as altitude increases.

b. lifting dumbbell weight at 20-degree angle from the body after a 45-degree angle