Even Physics Textbooks Tend to Get Friction Slightly Wrong

Even Physics Textbooks Tend to Get Friction Slightly Wrong

Let's consider a very basic physics problem involving pushing a block with a frictional force . Suppose I have a very low-friction cart with a constant-strength force pushing on it (in this case, it has a fan mounted on top).

Penn Jillette Performed a Séance at a Steven Spielberg Party

Penn Jillette Performed a Séance at a Steven Spielberg Party

This should have ruined the whole trick, except Spielberg actually picked the photo the magician needed him to. Find out more about Spielberg's bachelor party, and a few other of Jillette's magician secrets, in the video above.

Cantina Talk: But Really, What Are Sith Troopers?

Cantina Talk: But Really, What Are Sith Troopers?

Now, a new post on Making Star Wars has a theory, informed by rumors from unnamed sources: The Sith troopers, it declares, are part of a previously unknown fleet loyal to Emperor Palpatine that has been hidden in the outer limits of the galaxy for years, returning to deal with an unsuspecting threat posed by … the First Order, of all things.

Fact-Check the Physics of Captain America Hammering Thanos

Fact-Check the Physics of Captain America Hammering Thanos

If this interaction force is the only force acting on our two humanoids for the same amount of time, Captain America's change in momentum will be exactly opposite that of Thanos.

Let's Break Down the Physics of a Wickedly Curving Baseball

Let's Break Down the Physics of a Wickedly Curving Baseball

This change in momentum of the air produces a force on the ball in the other direction. The magnitude of the force depends on the velocity, the angular velocity, the area of the ball, the density of air and a Magnus coefficient (CM).

An Electric Pickup Truck Really Could Pull a Freight Train—Here's How

An Electric Pickup Truck Really Could Pull a Freight Train—Here's How

Here is a force diagram for a tiny object pulling a massive object with no friction. For the train (object B), a frictional force is pulling to the right.

Star Wars News: The End of 'Rise of Skywalker' Will Melt Your Mind

Star Wars News: The End of 'Rise of Skywalker' Will Melt Your Mind

The Real Deal: You might think you're prepared for this December's Star Wars: The Rise of Skywalker , but Kevin Smith wants you to know that you're probably not.

Great Stunt, Spider-Man! Now Let's Fine-Tune the Physics

Great Stunt, Spider-Man! Now Let's Fine-Tune the Physics

Now, if we put this vertical acceleration together with the fixed horizontal velocity , we get something special, called projectile motion. On the next jump, I get a vertical acceleration of –6.074, which is closer, but you can see that the fit is pretty janky.

A New Law Makes Bots Identify Themselves—That's the Problem

A New Law Makes Bots Identify Themselves—That's the Problem

The highly ambiguous law is tailored to address conversations that inspire purchases or sway votes, but it fails to carefully define what constitutes “influenc[ing] a vote in an election.” Is sharing legitimate news stories or voting locations a form of “influence?” After all, not all online automated accounts are malign; some are simply news or information dissemination services, while others are created by artists.

The Air Force's New Rescue Chopper Flies Farther Than Ever

The Air Force's New Rescue Chopper Flies Farther Than Ever

Carrying improvements like seats that swivel between patient-bearing stretchers and enemy-facing machine guns, the Combat Rescue Helicopter could enter service next year. The new Combat Rescue Helicopter, as the Air Force dubs it, comes with a suite of improvements over the HH-60 Pave Hawk it’s replacing, some of them long needed.

Palantir Manual Shows How Law Enforcement Tracks Families

Palantir Manual Shows How Law Enforcement Tracks Families

Security News this Week: Palantir Manual Shows How Law Enforcement Tracks Families. If you happened to buy the Blue Smart hair straightener from Glamorizer—perhaps not even realizing it had Bluetooth capability, because why would it?—then TechCrunch is sorry to report but hackers could totally seize your device, and well, change the temperature of the hot iron remotely, if they wanted to.

The Awesome Bowling Robot Is Surely Fake. Here's How to Tell

The Awesome Bowling Robot Is Surely Fake. Here's How to Tell

Motion of the Spinning Arm. I already have an estimate for the launch speed of the ball from the time it takes to get down the lane.

A Deadly Tick Virus, Extreme Seasonal Weirdness, and More News

A Deadly Tick Virus, Extreme Seasonal Weirdness, and More News

A deadly tick can make you allergic to bacon and carries a mystery virus, cities are turning to Waze for help with car accidents, and you might be paying too much for your PlayStation 4.

Physics Tricks to Make Steph Curry's Golf Show More Extreme

Physics Tricks to Make Steph Curry's Golf Show More Extreme

The fake force allows a rotating reference frame to act like a stationary one. In the non-rotating frame, the ball just moved along with a constant velocity—just as it should with no net forces acting on it.

How 9 People Built an Illegal $5M Airbnb Empire in New York

How 9 People Built an Illegal $5M Airbnb Empire in New York

In a lawsuit filed Wednesday, the city names real-estate agent Elvis Tominovic as the central figure in the “lucrative unlawful hotel operation.” The city wants Tominovic and 13 other people and businesses alleged to be involved in the scheme to turn over all revenue, properties, and proceeds from illegal rental activity; pay fines and damages; and shut down their listings.

What Adam Savage Needs to Know to Fly an Iron Man Suit

What Adam Savage Needs to Know to Fly an Iron Man Suit

That means the pilot can control the suit by just changing the arm positions and not even having to adjust the jet engine thrust. Here is a diagram looking from the side of the flying Iron Man:Notice that there is now a forward component of force from the back jet.

Post-Apocalyptic Survival Skills: How to Measure Acceleration

Post-Apocalyptic Survival Skills: How to Measure Acceleration

With that, I can find a force-acceleration equation for both masses. With an accelerating mass, the net force is NOT zero. Notice that if the two masses have the same value, the acceleration would be zero meters per second squared (that's good).

A Mythical Form of Space Propulsion Finally Gets a Real Test

A Mythical Form of Space Propulsion Finally Gets a Real Test

Over the course of 55 experiments, Tajmar and his colleagues registered an average of 3.4 micro-Newtons of force from the EmDrive, which was very similar to what the NASA team found.

The Physics of the Millennium Falcon's Jump to Hyperspace

The Physics of the Millennium Falcon's Jump to Hyperspace

To estimate the acceleration, we can look at the angular size of the back of the Falcon as it moves away. All I need to do is measure the position of the sides of the Falcon and use that to calculate the angular size in each frame of the video during the jump to hyperspace.

Distant Neutron Stars Could Reveal the Quirks of Quarks

Distant Neutron Stars Could Reveal the Quirks of Quarks

When the Large Hadron Collider smashes lead ions together, the collisions regularly reach temperatures of 5.5 trillion degrees Celsius, or 10,000 times hotter than the core of the sun.

Global Takedown Shows the Anatomy of a Modern Cybercriminal Supply Chain

Global Takedown Shows the Anatomy of a Modern Cybercriminal Supply Chain

On Thursday, police in six countries along with the US Justice Department and Europol announced the takedown of Goznym—linked with another operation known as Avalanche, an associated cybercrime operation that was largely dismantled in 2016 —including the arrest of five of its members across Bulgaria, Georgia, Moldova, and Ukraine.

Why a Golf Ball Compresses Like a Spring—Until It Shatters

Why a Golf Ball Compresses Like a Spring—Until It Shatters

An experiment with a paperclip reveals both its elastic and plastic properties, a distinction that's key to how any material compresses or deforms. plastic properties of a paperclip with a graph that looks something like this.

Why Amazon Is Giving Employees $10,000 to Quit

Why Amazon Is Giving Employees $10,000 to Quit

The company says more than 200 delivery partners have sprung up in the last year, but the US labor market remains extremely tight, and it’s not clear how many more people are in a position to join the program.

Feds Dismantled the Dark-Web Drug Trade—but It's Already Rebuilding

Feds Dismantled the Dark-Web Drug Trade—but It's Already Rebuilding

Judging by that buzzing trade, there's little hint that just the week before, global law enforcement announced the takedowns of two of the world's largest dark-web drug sites, known as Wall Street Market and Valhalla.

Calculate the G’s of Using an Ejection Seat to Blast Out of a Jet

Calculate the G’s of Using an Ejection Seat to Blast Out of a Jet

Even though the seat is actually accelerating downward (because of the gravitational force), it's good enough to get a linear fit and find an approximate post-rocket acceleration with the slope of this line at a velocity of 19.4 meters per second (43.4 mph).

A Physics Analysis of Every Jedi Jump in All of Star Wars

A Physics Analysis of Every Jedi Jump in All of Star Wars

A Physics Analysis of Every Jedi Jump in All of Star Wars. For these Jedi jumps in Star Wars, it's plausible to estimate the distance scale by looking at things like Ewan McGregor (height of 1.78 meters) or Liam Neeson (height of 1.93 meters).

Why the Air Force Is Embedding Airmen at Carnegie Mellon

Why the Air Force Is Embedding Airmen at Carnegie Mellon

So Pittsburgh will be one of the places where the Air Force puts a cell of airmen, based on our long partnership with Carnegie Mellon, focused on autonomy and robotics.

The Physics of a Bolt Smashing a Watermelon (or Your Brain)

The Physics of a Bolt Smashing a Watermelon (or Your Brain)

If the bolt hit a hard surface and stopped in a super short period of time, the impact force would be much larger than if it hit a soft surface (soft like a watermelon head).

Census Citizenship Question Riles Tech and Privacy Groups

Census Citizenship Question Riles Tech and Privacy Groups

"Our position is that collecting citizenship information from every person in the country and transferring it in bulk to another federal agency potentially for criminal law enforcement is a gross invasion of privacy that isn't justifiable," says John Davisson, counsel at EPIC.The organization filed a lawsuit in the US District Court in Washington DC, laying out much the same argument.

Estimate the Pulling Force of Boston Dynamics' Robo-Dog Army

Estimate the Pulling Force of Boston Dynamics' Robo-Dog Army

That's pretty close to the estimated friction from the robot dogs (maybe my values for the coefficients are off).What about pulling a truck uphill? They also have a decrease in the frictional force needed to pull the truck up the incline.

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