9.3 - Terminal speed

Question 1

why does the drag force depend on, for an object moving through a fluid

(3)

Answer 1

• object speed
• object shape
• fluid viscosity

Question 2

describe the motion of an object falling through a fluid

• speed & forces

Answer 2

• object initially released from rest
• its speed increases as it falls

(RF = difference between weight and drag force)

• as object increases in speed, drag force increases = decreased RF
• if continues falling, object reacher terminal speed (weight = drag force)

Question 3

the equation to calc the RF on an object falling through fluid

Answer 3

RF = mg - D

(D = drag forces)

Question 4

the equation to calc the acceleration on an object falling through fluid

Answer 4

a =(mg - D)/m

a = g -(D/m)

Question 5

what does a top speed of a motor vehicle depend on

(2)

Answer 5

engine power

aerodynamics

Question 6

the equation to clac the acceleration of a powered vehicle moving across a flat surface

Answer 6

a = (Fe - Fr) / m

Fe = motive force

Fr = total resistive forcec

Question 7

describe the forces acting on a powered vehicle when its reached max speed

Answer 7

RF = 0

engine force = restive force