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Can the value of friction force ever exceed value of applied force?

No. You've discovered the Class 2 Lever, which places the load between the input force and the fulcrum. You have correctly calculated that the friction force is 4 times the input force. The reason for ...
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6 votes

Can the value of friction force ever exceed value of applied force?

First, there is an important qualification to "the value of friction force can never be greater than the applied force". This refers to static friction. Indeed, you pose a scenario where &...
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4 votes

Morin 2.16 - Balancing a semi-infinite stick

The author replaces $x_0$ with $x_0+dx_0$ both in the integral limits and in the integrand because this is a way of obtaining contributions to the derivative wrt $x_0$. You can have both contributions ...
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4 votes
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Morin 2.16 - Balancing a semi-infinite stick

When differentiating an integral with respect to limits, according to the Wikipedia page on the Leibniz integral rule \begin{equation} \frac{\text{d}}{\text{d}x}\left( \int_{a(x)}^{b(x)}f(x,t)\text{d}...
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3 votes

Rotating a lever — small end has more force but less speed?

There are two errors here. First, $ F_{2} = F_{1}\frac{R}{r} $ is about the balancing of two torques in static equilibrium. That is, the usually case where this holds is where $F_1 R$ is one torque, ...
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2 votes
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Traction Torque Effect On A Rotating Wheel

engineers usually say that the wheels driving torque is always equal to the traction force times the radius of the wheel. That's a simplification where the mass of the wheel is insignificant compared ...
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2 votes

Can the value of friction force ever exceed value of applied force?

To answer the question in the title, the friction force can be larger than the normal force that is producing it. There is no restriction. Coefficients of friction larger than 1 are not common in ...
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1 vote

The utility of HorsePower vs Torque

Neglecting air resistance and other forms of drag the general expression for acceleration as a function of engine power (regardless of gearing etc) is $$ a = \frac{P}{m\, v} \tag{1}$$ Note: All ...
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1 vote

The utility of HorsePower vs Torque

Which vehicle would experience greater acceleration (G) The acceleration is given by the force at the road. The force at the road is in turn specified by taking the power and dividing by the speed. ...
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1 vote
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High school Momentum/Torque problem

The problem should also state "assume the assume the point where the base remains on the floor does not move". Consider the torque to turn the set over, about the fixed point of the base on ...
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1 vote
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Which configuration is better for this electric motor?

I think there is some things that need to be cleared up. If $l_1$ is longer is means that the electric motor will create more torque since the force from the lorentz force will be further from the ...
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1 vote

Traction Torque Effect On A Rotating Wheel

If the torque due to traction equals that of the motor the angular acceleration is indeed zero. Obviously when a vehicle accelerates the driving force of the motor overcomes that of the friction. It ...
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1 vote

Traction Torque Effect On A Rotating Wheel

This wheel would never accelerate as two opposing torques of equal magnitude are acting on the wheels such they should cancel each other creating ZERO acceleration. No. You need to learn what free ...
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1 vote
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Rotating a lever — small end has more force but less speed?

What accelerates object A is not the force $F_1$ that you applied to it, it's the net force that it experiences. $F_1$ is one component of the net force, but there is also a reaction force from the ...
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1 vote
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Work done By Internal Forces Inside a hinged Rotating Rod

In general, internal forces can do non-zero work on a particle system, and thus change kinetic energy of particles in the system. This is taken into account in the work-energy theorem: work of all ...
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1 vote

Work done By Internal Forces Inside a hinged Rotating Rod

For these types of problems they are treated as a rigid body and as such if you broke down the rod into smaller pieces or particles the distance between adjacent particles within the rigid body would ...
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1 vote

Traction Torque Effect On A Rotating Wheel

Here is a much simplified schematic diagram of the rear end of the transmission chain as a car is accelerating towards you. For the transmission shaft the net torque on it, $\tau_{\rm TE}-\tau_{\rm ...
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1 vote

Traction Torque Effect On A Rotating Wheel

For any mechanical system, every piece of it will obey Newton's laws. For a system like the one you've shown, each colored part will obey Newton's laws during operation (this analysis is usually done ...
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