# Tag Info

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The only condition for free fall as you said is that the motion of the body should be only under the influence of gravity alone. There should not be any effect of other forces like air resistance, viscous drag etc. The condition depends on the property of the material under free fall. For example, if the body has a certain mass as well as charged, it causes ...

1

All the example you have quoted can be regarded as oscillatory in that in some way the motion repeats itself be it with changing amplitude and/or with changing period. As an example would one use the term oscillatory for the motion of a pendulum? I think for most people the answer would be "Yes" even though both the period and the amplitude of the ...

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1)For net wt 100kg to be lifted in air ,lift has to be greater than equal to 100kg. 2)To produce minimum of 100kg lift ,it depends upon shape,size,weight,angle of attack of wing and lastly speed /velocity of wing/plane.Further velocity depends upon thrust ,total mass and drag(shape of flying machine). In simple words only Forward thrust,total weight and ...

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Take a future-directed timelike curve $\gamma= \gamma(\tau)$, $\tau$ being the proper time along $\gamma$ in the spacetime $M$. Assume that $p = \gamma(0)$ is the initial point of $\gamma$. Fermi coordinates adapted to $\gamma$ are constructed this way. Consider an orthonormal basis of $T_pM$ with $e_0$ parallel to $\dot{\gamma}$. Transport the basis ...

0

What is the difference between the potential difference and potential energy of an electron? If I understand your question right, these terms are describing the same thing - one is just in a "per charge" version. Electric potential energy $U_e$ is the potential energy associated with one spot in the circuit. Electric potential or just potential $V$ is ...

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So the definition of angular momentum should be this: "Angular momentum is the product of the angular velocity of the body or system and its moment of inertia with respect to the rotation axis, and that is directed along the rotation axis". That's not a useful definition at all, because (i) it does not specify what this "moment of inertia" thing is, and ...

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Like Wikipedia says: "Moment is a combination of a physical quantity and a distance." This 'physical quantity' could be various things. To take the examples you mention: Moment of momentum (commonly known as angular momentum) is expressed as $\vec{L}=\vec{r}\times m\vec{v}$, and is a measure for the rotational momentum of an object around some axis. Moment ...

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Rotation is absolute. And in any non-rotating reference frame, the earth and the sun (ignoring all the other bodies in the solar system, and the rest of the universe) both revolve around their common center of mass. Since the mass of the sun is so much greater than the mass of the earth, it is pretty close to saying that the sun is stationary and the earth ...

0

Since work done by a force $\vec F$ undergoing a displacement $d\vec r$ is defined as $\vec F \cdot d\vec r$ when this dot product is positive the force and displacement are in the same direction and is negative when they are in opposite directions. The work done by a frictional force does not always have to be negative. Imagine a block $A$ on top of block ...

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Force is a vector, meaning magnitude and direction. Work done by a force is relative to the direction of a force is the scalar value obtained by performing the vector dot product of the force and the displacement (which is also a vector). If something isn't coming out to what you expect when you compute work, make sure you have the right magnitude and ...

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First of all, there are two general types of free energy: Gibbs and Helmholtz. Helmholtz free energy is $F=U-TS$, whereas the Gibbs free energy has an additional term that accounts for the work done on the environment by the system, $G=F+pV$. If you're modelling a system in a vacuum or a gas, say, then you'd typically use Helmholtz, whereas in a solution ...

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You should plug in the horizontal force acting on the object if you want to know the work done by this force. Due to friction heating up the plane not all of this work is converted in the objects kinetic energy. PS: I assume you meant "while calculating the work" rather than "while calculating the force"..

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I'll assume you meant to say "Rheological definition of friction". Rheology deals with the friction of fluid layers against one another and with any solid boundaries. The factors of fluid viscosity determine the frictional forces exterted within a fluid and with its boundaries. A brief overview of the principles, mathematics can be found here

2

Theese concepts usually arise in rigid body mechanics. So consider a rigid body which is a set of points in which the distance between any two points do not change. If this is too abstract you can just think of a piece of rock. One talks of translational motion when the body moves along a straight line, or more exactly when every point of the body travels ...

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I haven't given the exact definitions, but instead given examples on what each of the three are. This will help you get your head around the topic, and be able to get more understanding when you encounter the problem again later. Translation is when the centre of mass of a body moves from one point to another. An example is just pushing a book along a ...

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In electrical circuits impedance $Z = \dfrac {V_{\text{peak}}}{I_{\text{peak}}}$ or $\dfrac {V_{\text{rms}}}{I_{\text{rms}}}$ If $I = I_{\text{peak}} \sin \omega t$ and $V_L = L \dfrac {dI}{dt}$ then $V_L = \omega L I_{\text{peak}}\cos \omega t = V_{\text{peak}} \cos \omega t$ This gives $Z = \omega L$ However look at the ratio of the instantaneous ...

1

It is indeed the ratio of $V_{max}$ to $I_{max}$ but only when you are talking about a sinusoidal voltage source and a "linear" component. For example, consider the charging curve of a capacitor: It would be incorrect to assume the impedance of this circuit is just $V_{max}\over I_{max}$ as this circuit behaves in a little bit of a more complex fashion. ...

1

Impedance expresses a linear response relation between current and voltage, but is usually considered only for fourier-transformed voltages and currents. I.e., it is a complex function $Z(\omega)$ so that: $$V(\omega) = Z(\omega) I(\omega).$$ The proper real-time analogue would not be the instantaneous ratio of voltage to current, but rather a relation that ...

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Wikipedia states In quantitative terms, it is the complex ratio of the voltage to the current in an alternating current (AC) circuit. https://en.m.wikipedia.org/wiki/Electrical_impedance

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The above answer is correct , though you may like to hear what i am saying : Suppose a person is applying force 5 Newton in -> direction. Friction is 5 Newton in <- direction. (( The person had to start moving box by applying a slightly larger force: say 5.001 Newton at time=0. so that an instantaneous acceleration increases the velocity to some ...

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