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2. ## AP2 appendix A p 291 question 6 - charging electroscope

Connecting to ground provides an infinite supply of electrons (or can be an infinite sink of electrons). If you ground a metal rod, and hold a negative rod near an end, negative charges will be repelled from the rod into the ground. If you then disconnect the rod from the ground, no charges can enter or leave the rod, so you're left with a net positive charge on the rod.
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5. ## AP2 appendix A p 291 question 6 - charging electroscope

Thanks for the reply, But if I ground the end of the electroscope / metal rod that has an induced positive charge then electrons will flow from the earth to balance that net positive charge. When the negatively charged rod is removed from the electroscope the electroscope will then have a net negative charge - the opposite of what was asked for in the question.
6. ## Graphing the Rotational Inertia of an Irregular Shape

We determine what data to collect to create a graph with rotational inertia as the slope of the best-fit line. #RotationalInertia - Then we collect the data and determine the rotational inertia of an irregular shape. Want Lecture Notes? This is an AP Physics 1 Topic. Content Times: 0:11 The problem 0:46 Free Body Diagram 1:31 Net Torque 3:01 Trial #1 3:52 Angular Acceleration 5:20 12 Trials and Graph 6:29 Deriving Units Multilingual? Please help translate Flipping Physics videos! Previous Video: Painter on a Scaffold - Don't Fall Off!! Please support me on Patreon! Thank you to Christopher Becke and Faiaz Rahman for being my Quality Control Team for this video.
7. ## AP2 appendix A p 291 question 6 - charging electroscope

Page 78 in the book talks about charging by induction. This section should help you out. It doesn't matter which part of the metal rod is grounded, since it's a conductor.
8. ## AP2 appendix A p 291 question 6 - charging electroscope

I am trying to understand the answer to this question. If a negatively charged rod is brought near the knob at the top of the electroscope then the electrons in the electroscope will be pushed to the end with the leaves (the knob will assume a net positive charge). If the aim is to finish with a positively charged electroscope then a grounding wire / finger would have to be applied near the leaf end of the electroscope to give the excess electrons a path to earth. The given answer does not specify which part of the electroscope is grounded, but since only the knob is accessible, the rest being in the glass bulb, the implication is that the knob is grounded. It seems to me that grounding the knob would cause electrons to flow from earth onto the positively knob and when the ground is broken and the rod removed the result would be a negatively charged electroscope.
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10. ## Painter on a Scaffold - Don't Fall Off!!

Example: What is the closest to the end of a 93 g uniform meterstick you can place a 200.0 g object and have the system stay balanced? The meterstick is supported at the 20.0 cm and 80.0 cm marks. Want Lecture Notes? This is an AP Physics 1 Topic. Content Times: 0:03 A scaffold 0:33 The problem 1:28 Free body diagram 2:06 Net torque 3:34 Force Normal demo 4:28 Solving the problem 6:17 Testing our answer Next Video: Graphing the Rotational Inertia of an Irregular Shape Multilingual? Please help translate Flipping Physics videos! Previous Video: Placing the Fulcrum on a Seesaw Please support me on Patreon! Thank you to Scott Carter, Christopher Becke, and Jonathan Everett for being my Quality Control Team for this video.
11. ## Placing the Fulcrum on a Seesaw

Example: A 200.0 g mass is placed at the 20.0 cm mark on a uniform 93 g meterstick. A 100.0 g mass is placed at the 90.0 cm mark. Where on the meterstick should the fulcrum be placed to balance the system? Want Lecture Notes? This is an AP Physics 1 Topic. Content Times: 0:01 Seesaw 0:33 The problem 1:28 The fulcrum 2:14 Free body diagram 2:38 Net force 3:35 Net torque 5:49 Combining equations 7:11 Testing our answer 8:11 Alternate solution Next Video: Painter on a Scaffold - Don't Fall Off!! Multilingual? Please help translate Flipping Physics videos! Previous Video: Introductory Rotational Equilibrium Problem Please support me on Patreon! Thank you to Scott Carter, Christopher Becke, and Jonathan Everett for being my Quality Control Team for this video.
12. ## Fluids and projectile motion

All the best to you and yours as well! Merry Christmas!
13. ## Fluids and projectile motion

Thanks Dan, wishing you & your family a great Christmas
14. ## Fluids and projectile motion

I would think the final pressure would be atmospheric... 🙂
15. ## Fluids and projectile motion

Hi, I'm really stuck on this problem and I don't know how to solve it. I have a syringe full of water laid horizontally at a height of 4,9 meters from the ground. I want to calculate the distance that the water coming out of the syringe travels before hitting the ground (it acts like a projectile). A pressure of 100 Pa is applied to the "back" of the syringe (the thing of the syringe that when pushed expels water). The diameter of the back is 1 cm whereas the diameter of the little exit at the front is 2 mm. This is my strategy: I calculate the areas (by making sure to convert cm and mm to meters) and apply the continuity equation A1v1 = A2v2 so that I can find the ratios between the velocities. I then use Bernoulli's equation to find the final velocity of the water getting out of the syringe. Then I use one of the kinematics equations to find the distance travelled by the water using the final velocity of the syringe as the initial velocity of the projectile motion. The problem is that I cannot find the final pressure in the Bernoulli's equation. What I mean by that is that I have this: P1 + 1/2ρv12 + ρgy1 = P2 + 1/2 ρv22+ ρgy2 ρgy1 and ρgy2 cancel out To find v2 I need the final pressure P2 but I don't have it. How can I find it? Thanks! I appreciate any help that comes my way.
16. ## Introductory Rotational Equilibrium Problem

A uniform 0.093 kg meterstick is supported at the 15 cm and 92 cm marks. When a 0.250 kg object is placed at the 6.0 cm mark, what are the magnitudes of the forces supporting the meterstick? Want Lecture Notes? This is an AP Physics 1 Topic. Content Times: 0:07 The problem 1:35 Summing the forces 2:55 Summing the torques 5:17 Combining equations 6:04 Torque distances 7:14 The units!! 8:20 Finding Force Normal 1 9:26 Testing our answers Next Video: Placing the Fulcrum on a Seesaw Multilingual? Please help translate Flipping Physics videos! Previous Video: Rotational Equilibrium Introduction (and Static Equilibrium too!!) Please support me on Patreon! Thank you to Scott Carter, Christopher Becke, and Jonathan Everett for being my Quality Control Team for this video.
17. ## Rotational Equilibrium Introduction (and Static Equilibrium too!!)

An introduction to Rotational Equilibrium with a review of Translational Equilibrium and demonstrations. Wait there’s more … Static Equilibrium! Want Lecture Notes? This is an AP Physics 1 Topic. Content Times: 0:07 Reviewing Translational Equilibrium 1:21 Visualizing Translational Equilibrium 2:07 Rotational Equilibrium Introduction 3:09 Visualizing Rotational Equilibrium 4:22 Static Equilibrium Next Video: Introductory Rotational Equilibrium Problem Multilingual? Please help translate Flipping Physics videos! Previous Video: (2 of 2) Measuring the Rotational Inertia of a Bike Wheel Please support me on Patreon! Thank you to Scott Carter, Christopher Becke, and Jonathan Everett for being my Quality Control Team for this video.
18. ## (2 of 2) Measuring the Rotational Inertia of a Bike Wheel

1) Calculating if our answer makes sense. 2) Why can’t we sum the torques on everything? 3) Finding the force of tension. Want Lecture Notes? This is an AP Physics 1 Topic. Content Times: 0:01 Reviewing from last time 1:08 Does it make sense? 2:41 Calculating the fraction 3:41 Sum the torques on everything? 6:07 Solving for force of tension 8:24 Testing our answer Next Video: Rotational Equilibrium Introduction (and Static Equilibrium too!!) Multilingual? Please help translate Flipping Physics videos! Previous Video: (1 of 2) Measuring the Rotational Inertia of a Bike Wheel Please support me on Patreon! Thank you to Scott Carter, Christopher Becke, and Jonathan Everett for being my Quality Control Team for this video.
19. ## (1 of 2) Measuring the Rotational Inertia of a Bike Wheel

That’s right, we actually measure the rotational inertia of a bicycle wheel. How cool is that? Want Lecture Notes? This is an AP Physics 1 Topic. Content Times: 0:10 Basic setup 0:44 Free Body Diagram 1:30 Finding net torque 3:10 Finding force of tension 4:51 Linear and angular acceleration 5:42 Uniformly angularly accelerated motion 7:00 What do we need to know? 7:35 Solving the problem Next Video: (2 of 2) Measuring the Rotational Inertia of a Bike Wheel Multilingual? Please help translate Flipping Physics videos! Previous Video: Introductory Rotational Form of Newton's Second Law Problem Please support me on Patreon! Thank you to Scott Carter, Christopher Becke, Jonathan Everett, and Faiaz Rahman for being my Quality Control Team for this video.
20. ## Introductory Rotational Form of Newton's Second Law Problem

A basic rotational form of Newton’s Second Law problem with only one force. Want Lecture Notes? This is an AP Physics 1 Topic. Content Times: 0:08 The problem 1:17 Free Body Diagram 1:37 Summing the torques 3:44 The direction Next Video: (1 of 2) Measuring the Rotational Inertia of a Bike Wheel Multilingual? Please help translate Flipping Physics videos! Previous Video: Introductory Rotational Form of Newton's Second Law Problem Please support me on Patreon! Thank you to Scott Carter, Christopher Becke, Jonathan Everett, and Faiaz Rahman for being my Quality Control Team for this video.
21. ## Demonstrating Rotational Inertia (or Moment of Inertia)

Thank you to Arbor Scientific for letting me borrow their Rotational Inertia Demonstrator to … uh … demonstrate rotational inertia. Want Lecture Notes? This is an AP Physics 1 Topic. Content Times: 0:22 The Rotational Inertia Demonstrator 0:58 Rotational Inertia 1:40 Demonstration #1 2:00 Demonstration #2 2:55 Why always balanced? 4:30 Demonstration #3 5:27 Demonstration #4 Next Video: Introductory Rotational Form of Newton's Second Law Problem Want a Rotational Inertia Demonstrator? Multilingual? Please help translate Flipping Physics videos! Previous Video: Rotational Form of Newton's Second Law - Introduction Please support me on Patreon! Thank you to Scott Carter, Christopher Becke, Jonathan Everett, and Faiaz Rahman for being my Quality Control Team for this video.
22. ## Rotational Form of Newton's Second Law - Introduction

A very basic introduction to the rotational form of Newton’s Second Law of Motion by way of its translational form. Want Lecture Notes? This is an AP Physics 1 Topic. Content Times: 0:15 Newton’s Second Law 0:48 The rotational form 1:59 Using the equation 3:13 In words Next Video: Demonstrating Rotational Inertia (or Moment of Inertia) Multilingual? Please help translate Flipping Physics videos! Previous Video: Net Torque on a Door Problem Please support me on Patreon! Thank you to Scott Carter, Christopher Becke, Jonathan Everett, and Faiaz Rahman for being my Quality Control Team for this video.
23. ## Net Torque on a Door Problem

Three people push on a door. We determine the net torque. Want Lecture Notes? This is an AP Physics 1 Topic. Content Times: 0:07 Translating the problem 2:00 Solving the problem 3:07 Torque Direction! Next Video: Rotational Form of Newton's Second Law - Introduction Multilingual? Please help translate Flipping Physics videos! Previous Video: The Right Hand Rule for Torque Please support me on Patreon! Thank you to Christopher Becke and Scott Carter for being my Quality Control Team for this video.
24. ## The Right Hand Rule for Torque

The right hand rule for the direction of torque is described and demonstrated six times. Want Lecture Notes? Content Times: 0:26 The Right Hand Rule 0:47 Demonstration #1 1:27 Demonstration #2 2:37 Demonstration #3 3:20 Demonstration #4 3:40 Demonstration #5 4:24 Demonstration #6 Next Video: Net Torque on a Door Problem Multilingual? Please help translate Flipping Physics videos! Previous Video: An Introductory Torque Wrench Problem Please support me on Patreon! Thank you to Christopher Becke and Scott Carter for being my Quality Control Team for this video.

Hi Robin, and welcome! Your book is available in the Community --> Downloads section (from the same page where you purchase), but I've also e-mailed a copy to you for convenience. Thanks for the support!

Hi! I just downloaded the digital regents book - - where do I go to access??
27. ## An Introductory Torque Wrench Problem

A problem involving forces on a wrench is used to determine the torque exerted by the wrench. A “cheater pipe” is also added. Want Lecture Notes? This is an AP Physics 1 topic. Content Times: 0:07 Translating the problem 2:35 Solving the problem 3:06 Arguing about the angle 4:44 Adding a “Part B” 5:40 Demonstrating the “cheater pipe” Next Video: The Right Hand Rule for Torque Multilingual? Please help translate Flipping Physics videos! Previous Video: Torque Introduction Please support me on Patreon! Thank you to Christopher Becke and Scott Carter for being my Quality Control Team for this video.
28. ## Torque Introduction

Translational and Rotational motion are demonstrated and reviewed. Torque is introduced via the equation and several door opening demonstrations. Moment arm or lever arm is defined and illustrated. Want Lecture Notes? This is an AP Physics 1 topic. Content Times: 0:06 Translational and Rotational Motion 0:58 Defining Torque 1:53 The torque equation 2:59 Door example #1 4:56 Door example #2 6:11 Door example #3 6:58 Defining moment arm 9:18 Torque units Next Video: An Introductory Torque Wrench Problem Multilingual? Please help translate Flipping Physics videos! Previous Video: Moments of Inertia of Rigid Objects with Shape Please support me on Patreon! Thank you to Christopher Becke and Scott Carter for being my Quality Control Team for this video.
29. ## Moments of Inertia of Rigid Objects with Shape

The moment of inertia of a system of particles equation is used to estimate six different moments of inertia of rigid objects with constant density. Want Lecture Notes? This is an AP Physics 1 topic. Content Times: 0:10 Visualizing the examples 1:09 How we estimate 2:16 Thin rod - center of mass 2:57 Thin rod - one end 4:00 Thin, hollow cylinder - long cylindrical axis 6:32 Solid cylinder - long cylindrical axis 8:23 Solid sphere - center of mass 9:11 Thin, hollow sphere - center of mass 10:31 Important review points Next Video: Torque Introduction Multilingual? Please help translate Flipping Physics videos! Previous Video: Eggs in a Carton Moment of Inertia Problem Please support me on Patreon! Thank you to Christopher Becke, Andres Ramos, and Aarti Sangwan for being my Quality Control Team for this video.

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