Tagged Questions
2
votes
5answers
162 views
Forces acting on a point mass in a spinning rigid body
I have learned that all spinning objects will continue spinning even if no force is acting on it, and the tendency to do so is called moment of inertia. But I wonder about the fact that a single point ...
1
vote
0answers
47 views
Fading transition and rotation of and object in 2D
I'm looking for sources about I guess dynamics subject.
The model I'd like to solve is reduced to a question of:
How does a force applied on a certain point of an object results in both fading ...
0
votes
0answers
300 views
How to find Rotational and Translational Equilibrium of Hanging Masses on a Bar?
I am making a hanging mobile which needs to be done mathematically by calculating torque. The problem is, I can't seem to figure out how to solve for the distance of the two masses from the pivot ...
1
vote
1answer
256 views
Kinetic Energy And Rotational Motion
The problem is, "A metal can containing condensed mushroom soup has mass 220 g, height 11.0 cm and diameter 6.38 cm. It is placed at rest on its side at the top of a 3.00-m-long incline that is at ...
7
votes
4answers
455 views
Which direction will the yoyo move?
This question has been around the net for a while, and I haven't seen a good explanation for it:
A yo-yo is initially at rest on a horizontal surface. A string is pulled in the direction shown in ...
0
votes
2answers
2k views
Tensions And Pulleys With Masses
The problem I am working on is:
"A block of mass m1 = 1.80 kg and a block of mass m2 = 6.30 kg are connected by a massless string over a pulley in the shape of a solid disk having radius R = 0.250 m ...
0
votes
2answers
233 views
Force applied off center on an object
Assume there is a rigid body in deep space with mass $m$ and moment of inertia $I$. A force that varies with time, $F(t)$, is applied to the body off-center at a distance $r$ from its center of mass. ...
0
votes
2answers
490 views
How to interpret this vertical circular motion problem?
A bucket of water is tied to a rope and swung in a vertical circle.
The distance from the bucket centre to the axis of rotation is
$2.08m$. Calculate the angular velocity (in $rad s^{-1}$) of ...
1
vote
1answer
263 views
What techniques can be used to analyze a rod rotating about the edge of a table?
A uniform rod of length $4x$ is rotating
about the edge $O$ of the table. (The rod does not fall off the table.) The centre of mass $G$ of the rod is distance $x$ away from $O$. The rod is making ...
2
votes
1answer
416 views
Normal force in a compound pendulum (physical pundulum) system?
Consider a compound pendulum pivoted about a fixed horizontal axis, illustrated by the force diagram on the right:
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Okay, I can't figure out where the normal force on the pendlum should point ...
2
votes
2answers
203 views
What sustains a rigid body's rotation at its constant angular(rotational) speed?
Continuing from the following scenario from my previous question Centripetal force of a rotating rigid body? :
Consider someone pushing a roundabout in a playground. Initially the
roundabout is ...
1
vote
3answers
644 views
Centripetal force of a rotating rigid body?
Consider someone pushing a roundabout in a playground. Initially the
roundabout is stationary, but when it is pushed, it rotates with
increasing rotational speed.
The force of the push is ...
0
votes
1answer
323 views
Calculation for force generated by a rotating rectangular blade
When trying to calculate the lift force generated by a simple rectangular blade, I've found the following equation: $$F = \omega^2 L^2 l\rho\sin^2\phi$$ in which $\omega$ is the angular velocity, $L$ ...
2
votes
0answers
539 views
Forces and torques about the CENTER OF MASS of a physical pendulum
I'm currently stumped by the following situation. Say we've got a rectangular physical pendulum (think ruler with a hole-punch at one end).
It's trivial to analyze the motion of the pendulum with the ...
2
votes
3answers
492 views
Why do some satellites fall to Earth?
In another question How does Newtonian mechanics explain why orbiting objects do not fall to the object they are orbiting?, one can read an affirmative answer. They how do you explain satellites ...
