As a bacterium swims through water it propels itself with its flagella so as to overcome the frictional drag forces and move at, more or less, constant velocity of 100 micrometer/s for periods of time. If the frictional drag force on a bacterium is 0.1 N, how much work does the bacterium do in 1 s?

A) 1 milliJoule

B) 10 microJoule

C) 100 microJoule

D) 1 J

E) 100 milliJoule

Respuesta :

Answer:

B) 10 microJoule

Explanation:

Given

v = 100 micrometer/s

F = 0.1 N

t = 1 s

we get the displacement as follows

d = v*t  ⇒  d = (100 micrometer/s)*(1 s) = 100 micrometer

then we apply the formula

W = F*d*Cos ∅

⇒  W = (0.1 N)*(100 micrometer)*Cos 0°

⇒  W = 10 microJoule