A skydiver is falling through air at a speed that is one fifth of their eventual terminal speed. ?

Question

What is the acceleration at this instant in terms of g, the acceleration of gravity? Assume that their cross-sectional area, drag coefficient, and density of air remain constant.

a. 0.96g

b. g

c. 0.20g

d. 0.80g

e. 5.0g

Answer 1

m a = m g - c v^2

Terminal velocity (a=0) is given by

V = sqrt(m g / c)

Taking v = V/5 gives

m a = = m g - 1/25 m g 

a = 24/25g = 0.96 g