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PY105 pre-class video for session 34 - Fluids and Newton's second law
In this video, we start talking about fluids. The buoyant force, exerted by a fluid on an object, is compared to the normal force. The key idea in this video is that Newton's second law can be applied to determine the buoyant force.
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PY105 pre-class video for session 33 - Simple harmonic motion 2
This is the second video, of two, related to simple harmonic motion. In this video, we go over the basic equations we use that give an object's position, velocity, and acceleration, all as a function of time, when it is experiencing simple harmonic [...]motion. We also derive the expression for the angular frequency for a block that is experiencing simple harmonic motion because it is attached to an ideal spring, by analyzing the forces on it. Finally, we take a quick look at a simple pendulum, and derive the expression for its angular frequency.
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PY105 pre-class video for session 32 - Simple harmonic motion 1
In this video, we will introduce the concept of simple harmonic motion, using a block on a spring as our example system. To analyze this system, we will apply some familiar ideas. We'll start by looking at the force exerted on a block by a spring, [...]and then we'll go from there to think about the work done by the spring, and go on from there to define an equation for potential energy for springs. So, the system is a new one, but the concepts we'll be bringing in to analyze it are ones we have experience with.
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PY105 pre-class video for session 31 - Gravitation
In this video, we'll talk about more general equations for gravitational force and gravitational potential energy than the equations we've been using so far. Instead of good old mg, we'll use Newton's universal law of gravitation to look at the [...]gravitational force between two objects. Similarly, instead of mgh, we'll discuss a more general equation for gravitational potential energy, and then we'll apply that equation to look at the speed a projectile would have to have at the Earth's surface so it never came back down again. That speed is known as the escape speed.
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PY105 pre-class video for session 30 - Rotational kinetic energy
In this video, we introduce the concept of rotational kinetic energy, and then we apply it to a spinning figure skater. Because this is the last video on rotational motion, the video also includes a summary of the parallels between straight-line [...]motion and rotational motion.
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PY105 pre-class video for session 29 - Angular momentum
In this video, we introduce the concept of angular momentum. There are many parallels between linear momentum and angular momentum, so we apply what we know about linear momentum to angular momentum. We also discuss a spinning figure skater, which is [...]a common example of a system in which angular momentum is conserved (at least for a short time), and we talk about how to convert a linear momentum into an angular momentum.
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PY105 pre-class video for session 27 - Newton's second law for rotation
In this video, we introduce Newton's second law for rotation, which is the fact that the vector sum of all the torques acting on an object is the rotational inertia of the object multiplied by the object's angular acceleration. Newton's second law [...]for rotation is the rotational equivalent of Newton's second law, that the vector sum of the forces acting on an object equals the mas multiplied by the acceleration.
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PY105 pre-class video for session 28 - rolling
In this video, we'll talk about four issues that relate to rolling, specifically to rolling without slipping. Among these, we'll cover how rolling motion can be looked at as the superposition of pure translation and pure rotation; how to find the [...]net instantaneous velocity of any point on a rolling object; and what the shape of the path is for a single point on the edge of a rolling object.
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PY105 pre-class video for session 21 - power, and energy vs. force
In this video, we define the concept of power, which is a measure of the rate at which work is done. We also spend some time comparing our two main approaches for solving problems, either by applying energy conservation ideas or by analyzing forces [...]to find acceleration, and using that acceleration in the constant acceleration equations.
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