Hovercraft B/C

[MattChina]

I guess Ill ask one.
Lets start of easy:
If i drop a ball off a cliff of 100m. Assuming we are on earth and there is no air resistance, how long will it take for the ball to reach the ground.

[Adi1008]

I guess Ill ask one.
Lets start of easy:
If i drop a ball off a cliff of 100m. Assuming we are on earth and there is no air resistance, how long will it take for the ball to reach the ground.

Answer (Click to Show Hidden Text)

4.5 seconds

[MattChina]

I guess Ill ask one.
Lets start of easy:
If i drop a ball off a cliff of 100m. Assuming we are on earth and there is no air resistance, how long will it take for the ball to reach the ground.

Answer (Click to Show Hidden Text)

4.5 seconds

yep. Your Turn.

[Adi1008]

I guess Ill ask one.
Lets start of easy:
If i drop a ball off a cliff of 100m. Assuming we are on earth and there is no air resistance, how long will it take for the ball to reach the ground.

Answer (Click to Show Hidden Text)

4.5 seconds

yep. Your Turn.

Suppose an object of mass m is falling such that air resistance cannot be neglected. The object is roughly spherical and quite small, so the drag force is directly proportional to its velocity (viscous drag force, F = bv, where b is a constant of proportionality with units kg/s).

a. What is the acceleration of the object, in terms of m, g, b, and instantaneous velocity v?
b. What is the velocity of this object at any given instant?
c. What is the terminal velocity of the object, in terms of m, g, and b?

[UTF-8 U+6211 U+662F]

Suppose an object of mass m is falling such that air resistance cannot be neglected. The object is roughly spherical and quite small, so the drag force is directly proportional to its velocity (viscous drag force, F = bv, where b is a constant of proportionality with units kg/s).

a. What is the acceleration of the object, in terms of m, g, b, and instantaneous velocity v?
b. What is the velocity of this object at any given instant?
c. What is the terminal velocity of the object, in terms of m, g, and b?

Answer (Click to Show Hidden Text)

a. g + bv/m
b. gt+bd/m, where d is the distance that the object has fallen so far (not sure how to do it just in terms of time)
c. mg/b

[Justin72835]

Suppose an object of mass m is falling such that air resistance cannot be neglected. The object is roughly spherical and quite small, so the drag force is directly proportional to its velocity (viscous drag force, F = bv, where b is a constant of proportionality with units kg/s).

a. What is the acceleration of the object, in terms of m, g, b, and instantaneous velocity v?
b. What is the velocity of this object at any given instant?
c. What is the terminal velocity of the object, in terms of m, g, and b?

Answer (Click to Show Hidden Text)

a. g + bv/m
b. gt+bd/m, where d is the distance that the object has fallen so far (not sure how to do it just in terms of time)
c. mg/b

Answer 2.0 (Click to Show Hidden Text)

I got the same answer as UTF for Part A and C. For Part B, I got:

v=\frac{mg(1-e^{-bt/m})}{b}

EDIT: For some reason the LaTeX isn't working so I just posted the code

[UTF-8 U+6211 U+662F]

Okay, lemme restart this thread.

If velocity is the change in position with respect of time and acceleration is the change in velocity with respect of time, then what is the change in acceleration with respect of time.

Also note the new

Code: Select all

[answer]

tag

Click to Show Answer

hi

[IcsTam]

Okay, lemme restart this thread.

If velocity is the change in position with respect of time and acceleration is the change in velocity with respect of time, then what is the change in acceleration with respect of time.

Also note the new

Code: Select all

[answer]

tag

Click to Show Answer

hi

Click to Show Answer

Jerk

[UTF-8 U+6211 U+662F]

Okay, lemme restart this thread.

If velocity is the change in position with respect of time and acceleration is the change in velocity with respect of time, then what is the change in acceleration with respect of time.

Also note the new

Code: Select all

[answer]

tag

Click to Show Answer

hi

Click to Show Answer

Jerk

Yep, your turn!

[IcsTam]

What is the difference between turbulent and laminar flow? How does Reynold's number pertain to these concepts? What value (or range of values) distinguishes between turbulent and laminar flow?