All Questions
Tagged with inertia homework-and-exercises
18
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Evolution of a rotating system in which mass continually leaks [closed]
this might be a trivial problem but me and a friend have failed to solve it. This is not homework, it actually relates to a book of mine but that is of no interest. Imagine the following;
Two masses $...
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Newton first law of motion
The State of rest and the state of uniform linear motion are equivalent. Why?
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Moment of inertia of a rotating square toroid [closed]
I'm trying to work out the moment of inertia (i.e. what would be $I=mr^2$ for a point mass) of the volume of rotation around the y-axis of a square with side length a, at a radius along the x-axis R, ...
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Do objects need some time to know that the forces exerted on them are gone?
Okay, so I know how to solve this question, but I don't quite understand the concept behind it!
The solution simply states that the acceleration of m2 after the rope is cut will equal the force of ...
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Moment of inertia of a solid sphere; spot the mistake [closed]
What an I doing wrong?:
$I = \int r^2dm$
$M = \rho \frac{4}{3} \pi r³$
$dM = \rho \frac{4}{3} \pi 3r²dr = \rho 4 \pi r²dr$
$I = \rho 4π \int r^4dr = \rho 4π \frac{r^5}{5} = \frac{3Mr^2}{5} = \frac{3}{...
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Why are you accelerating yet remaining at a constant speed while going around a curve? [duplicate]
We have to write a rap in physics, and it has to answer a prompt he gave us on this packet. The prompt for the verse I am writing is:
Pretend you are driving a car on the freeway going 65 mph. The ...
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Simple mechanics : Bar stuck to a point on the ground: Inertia problem
So, given the following bar, stuck to the ground at point O, I know its mass, the angle it makes with the vertical axis that goes through the point O, I know the bar's length and its initial velocity, ...
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Energy required to stop a rotor
If I want to stop a rotor going 8750 rpm with a moment of inertia .0325 kg m^2 then do I just calculate the kinetic energy the rotor has and that's my answer? and if so would I make it negative
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Rotating the bucket in circular motion without spilling water
In the bucket experiment when the bucket reaches the top of the circle why will it have a normal force acting on the water downwards? Doesn't normal force oppose any other force? There is no force ...
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Angular velocity of disc from induced motion
I came across a question regarding linear momentum $L$ and it's conservation, however I tried and got confused. It reads: A $40kg$ girl stands on the very edge of a rotating disc of mass $50kg$ and ...
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Inertial pressure on in a rotating syringe
First question on stackexchange. Hopefully somebody can help me out. I'm struggling to express the following eloquently.
I have a rotating syringe tipped with a needle. rotation speed w, with radius ...
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Do lawn mowers still cut the grasses if they aren't attached to the ground?
A rotary lawn mower cuts the grasses by rotating it's sharp blade on it but if the grasses aren't attached to the ground will they still cut them?
What forces act on this system? I know the answer is ...
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Block on an incline moving right with an acceleration [closed]
The situation looks as follows:
The incline is moving rightwards with a constant acceleration
The forces on the picture are:
mg - weight, N - normal force, F - inertial force (already shown), since ...
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How do I calculate the experimental and theoretical rotational inertia of a point mass?
I'm getting some weird results from a calculation I'm doing and quite honestly, I'm pretty sure it's due to human error. I do have an apparatus involved for the experimental process for my lab but I ...
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Velocity of 2 balls with different masses on a moving train after the train brakes
Question
This is from my textbook:
There are 2 balls of the same size made of rubber and iron respectively kept on the smooth surface of a moving train. Which ball will move faster when the train ...
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