|
|
|
|
|
 |
Yes, there are mistakes that many people make when it comes to free-fall acceleration problems. I dispel many misconceptions and explain both why people think they are true and why they actually aren't. Oh, and there are some special effects too!
Content Times:
0:14 Review of the Basics of Free-Fall
1:04 1st Misconception - The acceleration on the way up is positive
2:09 2nd Misconception - The initial velocity going upward is zero
2:45 3rd Misconception - A thrown ball will accelerate faster than a dropped ball
4:00 Reminder - Velocity at the top is zero
4:29 4th Misconception - The acceleration at the top is zero
6:36 Review
Want Lecture Notes?
Previous Video:
Creating a Position vs. Time Graph using Stop Motion Photography
Next Video:
A Free-Fall Problem That You Must Split Into Two Parts
Found by Flipping Physics in One-Dimensional Motion
December 22, 2013 at 12:46 PM
Ages: 13 - 18
License: Proprietary
| Rating: |
|
Not Right For WatchKnowLearn
|
|
Views: 2468 |
|
|
| |
|
|
|
|
|
|
In the last days of the Civil War, the Confederate capital of Richmond falls after nine months under siege. General Lee and President Jefferson Davis flee the city as Union forces advance to reclaim Virginia. In this video clip, learn more about the fall of the confederate capitol. (2:55)
Found by CourtneyMorrison in Fall of Richmond
May 11, 2012 at 02:44 PM
Ages: 12 - 18
License: Proprietary
| Rating: |
|
Not Right For WatchKnowLearn
|
|
Views: 2218 |
|
|
| |
|
|
|
|
|
|
Although the United States withdrew all of their troops by 1972, the war continued in Vietnam until 1975, when the communist forces of North Vietnam finally captured South Vietnam's capital. In this video clip, learn about the fall of South Vietnam and how the country became unified into one communist state. (3:26)
Found by CourtneyMorrison in Fall of Saigon
July 23, 2012 at 06:23 PM
Ages: 13 - 18
License: Proprietary
| Rating: |
|
Not Right For WatchKnowLearn
|
|
Views: 1757 |
|
|
| |
|
|
|
|
|
|
The day after the fall of the Berlin Wall on November 20, 1989, President George H. W. Bush met with West German Foreign Minister Hans-Dietrich Genscher to discuss plans for the reunification of Germany. As a token of his gratitude to the United States, Genscher brought President Bush a piece of the Berlin Wall. In a press conference, Bush thanks the foreign minister for the gift. (00:32)
Found by CourtneyMorrison in Bush, Sr. Speeches
June 23, 2012 at 05:05 PM
Ages: 13 - 18
License: Proprietary
| Rating: |
|
Not Right For WatchKnowLearn
|
|
Views: 1571 |
|
|
| |
|
|
|
|
|
|
The video is 2:50 minutes long and provides the history of the rise and fall of the Mongol Empire, one of the largest empires in the history of the world. Once Genghis Khan was made ruler of all Mongols in 1206, the Mongols quickly expanded into Europe and Asia. Statistics include how violent these people were and how the soldiers started as youngsters. A good overview.
Found by freealan in Ancient Middle East
July 16, 2011 at 10:21 PM
Ages: 8 - 18
License: Undetermined
| Rating: |
|
Not Right For WatchKnowLearn
|
|
Views: 1348 |
|
|
| |
|
|
|
|
|
|
In this lesson we extend our knowledge of Uniformly Accelerated Motion to include freely falling objects. We talk about what Free-Fall means, how to work with it and how to identify and object in Free-Fall. Today I get to introduce so many of my favorites: the medicine ball, the vacuum that you can breathe and, of course, little g.
Content Times:
0:22 An Example of An Object in Free-Fall
0:54 Textbook definition of a freely falling object
1:11 We have not defined a "Force" so this is how we define Free-Fall
2:07 No Air Resistance (The Vacuum that You Can Breathe!)
3:10 What does it mean to be in Free-Fall? (The Acceleration due to Gravity)
4:41 The Acceleration due to Gravity - Not on Earth
5:24 g is not constant on Earth. Very close, but not quite
5:56 Common Misconception: Objects moving upward can be freely falling
6:35 Free-Fall is Uniformly Accelerated Motion
7:27 What does the negative mean in -9.81 m/s^2?
7:57 Is "g" positive or negative?
9:01 How can "g" be not constant and we can use UAM?
10:03 Does mass effect the acceleration due to gravity?
10:47 The Review
Want Lecture Notes?
Previous Video: Reviewing One Dimensional Motion with the Table of Friends
Next Video: Apollo 15 Feather and Hammer Drop
Found by Flipping Physics in One-Dimensional Motion
December 22, 2013 at 12:14 PM
Ages: 13 - 18
License: Proprietary
| Rating: |
|
Not Right For WatchKnowLearn
|
|
Views: 1297 |
|
|
| |
|
|
|
|
|
|
Hurricane Katrina makes landfall near New Orleans, Louisiana, as a Category 4 hurricane on this day in 2005. Despite being only the third most powerful storm of the 2005 hurricane season, Katrina was the worst natural disaster in the history of the United States. After briefly coming ashore in southern Florida on August 25 as a Category 1 hurricane, Katrina gained strength before slamming into the Gulf Coast on August 29. In addition to bringing devastation to the New Orleans area, the hurricane caused damage along the coasts of Mississippi and Alabama, as well as other parts of Louisiana. (02:06)
Found by CourtneyMorrison in August 21-31
September 19, 2012 at 04:08 PM
Ages: 12 - 18
License: Proprietary
| Rating: |
|
Not Right For WatchKnowLearn
|
|
Views: 1056 |
|
|
| |
|
|
|
|
|
|
Trace the rise and fall of the Mongol Empire which, under the leadership of Genghis Khan, became the largest contiguous land empire in history. (05:00)
Found by andrewvanzyl in "Mongol Invasion of Europe"-Series
September 2, 2019 at 09:28 AM
Ages: 15 - 18
License: Proprietary
| Rating: |
|
Not Right For WatchKnowLearn
|
|
Views: 831 |
|
|
| |
|
|
|
|
|
|
In this Pick of the Week video, teenage students will be introduced to "As Easy As Falling Off" by Lynne Rae Perkins. Summary--Ry is off on an epic summer adventure. Here's the catch: It's not anything like the summer adventure he had planned. Ry planned on going to camp, but on his way to camp, he found out there was no camp. (Long story.) Then Ry planned on just making a quick phone call home, but by the time he found someplace with cell phone reception, his train had taken off without him. (Long story.) Then Ry did some walking (long story), and some cross-country driving (long story), and some flying in a tiny little sea plane (long story), and then his adventure STILL wasn't over and I was sort of wondering why. In "As Easy as Falling Off the Face of the Earth," Lynne Rae Perkins is in top form in terms of the sheer beauty of her writing, but as for the rest, well, everything from plot to character left a lot to be desired. This critic did not care for this book pick. This is a great resource to entice and encourage upper grade readers. (1:32)
Found by porter1526 in 60 Second Recap Series
October 2, 2011 at 03:13 PM
Ages: 13 - 18
License: Proprietary
| Rating: |
|
Not Right For WatchKnowLearn
|
|
Views: 710 |
|
|
| |
|
|
|
|
|
|
This is a complicated free-fall problem where you have to identify that the velocity at the top of the path is zero in the y-direciton. Furthermore, you have to look at it from the perspective of the whole event and splitting the problem into two different parts. A classic free-fall acceleration example problem.
Content Times:
0:45 Reading the problem
1:12 Translating the problem to physics
3:04 Starting with the whole event
4:36 Splitting the problem into two parts
6:06 Solving part 1: Going up
8:17 Finishing the problem
9:05 An alternate solution
9:38 The review
Want Lecture Notes?
Next Video:
Dropping Dictionaries Doesn't Defy Gravity, Duh!
Previous Video:
Common Free-Fall Pitfalls
Found by Flipping Physics in One-Dimensional Motion
December 22, 2013 at 12:38 PM
Ages: 13 - 18
License: Proprietary
| Rating: |
|
Not Right For WatchKnowLearn
|
|
Views: 688 |
|
|
| |
|
|
|
|
|
|
Are your kids wondering: "Why do leaves change color in the fall?" This question came from Nikhil, a 1st-Grader from the US. (05:25)
Found by teresahopson in Trees
October 7, 2020 at 05:54 PM
Ages: 6 - 13
License: Proprietary
| Rating: |
|
Not Right For WatchKnowLearn
|
|
Views: 513 |
|
|
| |
|
|
|
|
|
|
In this video clip, Vietnam veteran Jack Smith recalls the horrors of the Vietnam war and the memories of fallen friends. (2:44)
Found by CourtneyMorrison in Vietnam Veterans
July 25, 2012 at 04:14 PM
Ages: 13 - 18
License: Proprietary
| Rating: |
|
Not Right For WatchKnowLearn
|
|
Views: 488 |
|
|
| |
|
|
|
|
|
|
Before the Sun never set on the British Empire; before Genghis Khan swept the steppe; before Rome extended its influence to encircle the Mediterranean Sea; there was ancient Assyria. Considered by historians to be the first true empire, Assyria’s innovations laid the groundwork for every superpower that has followed. Marian H Feldman details the rise and fall of the Assyrian Empire. Lesson by Marian H Feldman, animation by Naghmeh Farzaneh. (05:16)
Found by teresahopson in Ancient Assyrians
July 28, 2019 at 01:37 PM
Ages: 14 - 18
License: Proprietary
| Rating: |
|
Not Right For WatchKnowLearn
|
|
Views: 296 |
|
|
| |
|
|
|
|
|
|
I compiled all my favorite footage of colorful fall foliage and autumn cabins from all over New England. (13:28)
Found by teresahopson in Autumn/Fall
October 16, 2020 at 07:26 PM
Ages: 7 - 18
License: Proprietary
| Rating: |
|
Not Right For WatchKnowLearn
|
|
Views: 283 |
|
|
| |
|
|
|
|
|
|
Watch as FamilyFun shows you this Thanksgiving kids' craft! A pilgrim hat is a great craft idea because it helps them get excited about the holiday season. You'll need the templates, tape, a pencil, black, brown, and gold paper, scissors, and glue. To start the Thanksgiving craft, cut out the templates to trace them onto various pieces of paper. Cut a strip of the paper to wrap around your child's head. Attach the headband to the back of the hat body with glue. Next, glue on the brim, buckle, and the hatband. Tape the headband to stay in place at the size your child needs. This easy Thanksgiving craft works to make dress up even more festive this fall! You could even tweak this craft for kids to use other materials for other seasons or holidays. (00:56)
Found by teresahopson in Thanksgiving Activities
November 20, 2018 at 02:53 PM
Ages: 5 - 13
License: Proprietary
| Rating: |
|
Not Right For WatchKnowLearn
|
|
Views: 247 |
|
|
| |
|
|
|
|
|
|
Learn a life-saving self-rescue skill essential for all outdoors people who venture out into winter. By learning how to reduce your cold shock and get yourself out of the water with these techniques, you can save your life or help someone who has fallen through the ice to save theirs. This technique is designed for use in still water, such as a lake, and will work even if you are wearing bulky clothes. It allows you to move your body up onto ice that cannot support your standing weight, and teaches how to move over the ice until you reach ice with weight-bearing capacity. (09:28)
Found by teresahopson in Playing Outside
July 9, 2022 at 10:59 AM
Ages: 7 - 18
License: Proprietary
| Rating: |
|
Not Right For WatchKnowLearn
|
|
Views: 137 |
|
|
| |
|
|
|
|
|
|
Resource produced by WGBH and funded by the National Science Foundation. (01:37)"The Moon, Earth's natural satellite, seems to hover in the sky, unaffected by gravity. However, the reason the Moon stays in orbit is precisely because of gravity -- a universal force that attracts objects. With the right combination of speed and gravity, satellites can fall around, instead of into, the body that they orbit. In this animated video segment adapted from NASA, learn about how the Moon stays in orbit around Earth." (01:37)
Found by teresahopson in Moon Overview
November 7, 2021 at 08:15 AM
Ages: 9 - 16
License: Proprietary
| Rating: |
|
Not Right For WatchKnowLearn
|
|
Views: 106 |
|
|
| |
|
|
|
|
|
|
Learn how to draw a fall tree with us! All you need is a marker, paper, and something to color with. We use oil pastels to color our trees, but you can use anything to color yours. (06:59)
Found by teresahopson in Draw Foliage and Trees
November 3, 2022 at 10:35 AM
Ages: 7 - 18
License: Proprietary
| Rating: |
|
Not Right For WatchKnowLearn
|
|
Views: 64 |
|
|
| |
|
|
|
|
|
|
In this episode: we'll go through the rise and fall of ancient greek civilization. Through most of its history, Greece was poor. In the classical era, though, Greece was incredibly populated and very urbanized. Many surprisingly healthy Greeks lived in remarkably big houses and worked for high wages at specialized occupations. Middle-class spending drove sustained economic growth and classical wealth produced a stunning cultural efflorescence lasting hundreds of years. (12:10)
Found by teresahopson in History of Greece
November 12, 2021 at 03:26 PM
Ages: 14 - 18
License: Proprietary
| Rating: |
|
Not Right For WatchKnowLearn
|
|
Views: 44 |
|
|
| |
|
|
|
|
|
|
Music by Peter Nanasi. Early on this summer when I found myself down by Santa Rosa, AZ watching a gorgeous hail core fall on the stunning desert landscape, and then later that day staring at a haboob with a stacked-shelf cloud above it near the border of Mexico, I had a feeling it would be a unique monsoon. It's funny how every year is different. That's the beauty of chasing the summer storm season out here in the desert southwest. You never know what's going to happen or what you might see. (08:07)
Found by teresahopson in Rain
May 11, 2020 at 02:13 PM
Ages: 11 - 18
License: Proprietary
| Rating: |
|
Not Right For WatchKnowLearn
|
|
Views: 33 |
|
|
| |
|
|
|
|
|
|
This video explains the process of the leaves changing. The repetition is great for ESL students (2:25)
Found by stephanie.green in Autumn/Fall
October 26, 2011 at 05:32 PM
Ages: 3 - 8
License: Undetermined
| Rating: |
|
Not Right For WatchKnowLearn
|
|
Views: 7593 |
|
|
| |
|
|
|
|
|
|
This video offers some great images of this natural wonder of the world. (03:43)
Found by Barb in Canadian Geography
August 19, 2009 at 03:32 PM
Ages: 7 - 12
License: Undetermined
| Rating: |
|
Not Right For WatchKnowLearn
|
|
Views: 7126 |
|
|
| |
|
|
|
|
|
|
This video explains how, in 1453, the Ottoman conquered the Byzantine Empire's capital, Constantinople. The conquering was lead by Sultan Mehmed II of the Ottoman Empire. There isn't any narration and the text movies rapidly so the video may need to be stopped at times for discussion. Some of the comments are intended as first person narrative. Sound can be muted. (08:22)
Found by freealan in Ancient Asia
November 6, 2011 at 01:48 PM
Ages: 12 - 18
License: Proprietary
| Rating: |
|
Not Right For WatchKnowLearn
|
|
Views: 6100 |
|
|
| |
|
|
|
|
|
|
This humorous video shows examples to help explain the differences between the theories of gravity provided by Aristotle and Galileo. After the first experiment have the students reach a conclusion about which scientist was right. Let the video play to the end and see which students were correct. A good lesson. (05:53)
Found by freealan in Gravity
June 14, 2012 at 10:46 AM
Ages: 8 - 18
License: Undetermined
| Rating: |
|
Not Right For WatchKnowLearn
|
|
Views: 6009 |
|
|
| |
|
|
|
|
|
|
Found by IwatchIknow in World History
July 19, 2013 at 11:09 AM
Ages: 16 - 18
License: Public Domain
| Rating: |
|
Not Right For WatchKnowLearn
|
|
Views: 5903 |
|
|
| |
|
12345678
(51 - 75 of 200)
|