What is Angular motion: Definition and 82 Discussions
In physics, circular motion is a movement of an object along the circumference of a circle or rotation along a circular path. It can be uniform, with constant angular rate of rotation and constant speed, or non-uniform with a changing rate of rotation. The rotation around a fixed axis of a three-dimensional body involves circular motion of its parts. The equations of motion describe the movement of the center of mass of a body. In circular motion, the distance between the body and a fixed point on the surface remains the same.
Examples of circular motion include: an artificial satellite orbiting the Earth at a constant height, a ceiling fan's blades rotating around a hub, a stone which is tied to a rope and is being swung in circles, a car turning through a curve in a race track, an electron moving perpendicular to a uniform magnetic field, and a gear turning inside a mechanism.
Since the object's velocity vector is constantly changing direction, the moving object is undergoing acceleration by a centripetal force in the direction of the center of rotation. Without this acceleration, the object would move in a straight line, according to Newton's laws of motion.
Homework Statement
I have a question that I am unsure of how to answer
A round metal bar is machined at a cutting speed of 90.m.min, if the diameter of the bar is 80mm determine...
a. The chuck speed in rad.s and rev.min
If it takes 3s to get to this speed from rest (0)
b. What...
Homework Statement
An electric motor rotating a workshop grinding wheel at a rate of 90 rev/min is switched off. Assume constant negative angular acceleration of magnitude 2.50 rad/s2.
(a) How long does it take for the grinding wheel to stop?
(b) Through how many radians has the wheel...
Homework Statement
When a wheel is rotated through an angle of 35o, a point on the circumference travels through an arc length of 2.5m. When the wheel is rotated through angles of 35 radians and 35 revolutions, the same point travels through arc lengths of 143m and 9.0 x 102m, respectively...
I am trying to answer a question, but I don't really understand what is being asked.
If you were to plot angular velocity against time and there was not force of acceleration explain what the curve would look like.
I would guess a straight horizontal line since angular acceleration is the...
I'm stuck on this question: A rock stuck in the tread of a 59.0-{\rm cm}-diameter bicycle wheel has a tangential speed of 3.40 m/s. When the brakes are applied, the rock's tangential deceleration is 1.00 m/s^2.
a) What is the magnitudes of the rock's angular velocity at t = 1.70 s?
b) What...
Homework Statement
A small object with mass 3.90 kg moves counterclockwise with constant speed 5.40 m/s in a circle of radius 5.00 m centered at the origin. It starts at the point with position vector (5.00i + 0 j) m. Then it undergoes an angular displacement of 8.00 rad.
(a) What it its...
Homework Statement
The shape of the arch is defined by a sine function with a = 0.2 and the width of the arch is 1m. The velocity v is constant at 2m/s. What is the velocity at point P when x=0.25m?
The Attempt at a Solution
So since v is just in the x-direction, I figured that's the vx...
The driver of a car traveling at 12.0 m/s applies the brakes and undergoes a constnant decelertion of 1.90m/s^2.
How many revolutions does each tire make before the car comes to a stop assuming that the car does not skid and that the tires of radii of 0.40 m? answer in units of rev.
I used...
The driver of a car traveling at 12.0 m/s applies the brakes and undergoes a constnant decelertion of 1.90m/s^2.
How many revolutions does each tire make before the car comes to a stop assuming that the car does not skid and that the tires of radii of 0.40 m? answer in units of rev.
I used...
The wheel on an upside down bike moves through 15 rad in 5 seconds. What is the wheel's angualr acceleration if its initial angular speed is 2.4 rad/s. Answer in units of rad/s^2
I used the equation ω(final) = ω(initial)+αt and solved for α however, I did not get a correct answer. Can anyone...
I am interested in how impulse turbines work. Supposing a mass of water (in kilograms), m, is expelled by a jet at a given velocity (in meters per second), v, its momentum (in Newton-seconds), p, is the product of these quantities: p = mv. Also, a paddlewheel’s angular momentum (in...
Does the theory of relativity include angular motion? Say we have one body synchronously orbiting a motionless body. It can also be viewed as two motionless bodies and one is spinning while the other is not. (i.e. if you were on the moon staring at earth, you would not witness orbital...
[SOLVED] Angular motion with constant acceleration
Homework Statement
Homework Equations
\varpi= \varpi(inital) + \alphat
The Attempt at a Solution
I understood part A and Part b,
What I don't understand is how to do Part C.
What I did was divide the average angular velocity...
1. A rigid body, starting at rest, rotates about a fixed axis with a constant angular acceleration α. Consider a particle a distance r from the axis. Express (a) the radial acceleration and (b) the tangential acceleration of this particle in terms of α, r and time t.
c) if the resultant...
Homework Statement
A figure skater completes a double axle (2 complete rotations) in 0.5 seconds. Calculate
the skater’s angular velocity and average angular velocity in a) deg/sec, and b) rad/sec.
If the skater manages to stop spinning in a time of 1.5 seconds,
what was the angular...
Homework Statement
A particle of mass m follows a path given by
r = (Xo + at^2)x + bt^3 y + ct z
where o, a, b and c are constants, t is the time. x, y , z should have hats on them showing they are position vectors (unit vectors).
1. Find the angular momentum L of the particle about...
Consider two particles A and B. The angular position of particle A, with constant angular acceleration, depends on time according to theta(t)=theta_0+omega_0t+alpha t^2. At time t=t_1, particle B, which also undergoes constant angular accelaration, has twice the angular acceleration, half the...
Homework Statement
A fan increases in speed from 500 to 700rev/sec in 30 seconds. What is the average angular acceleration during that time?
Homework Equations
The Attempt at a Solution
The answer i get for this one is
∝=(700-500 rev⁄sec)/3sec
any input appreciated
Homework Statement
A wheel starts from rest and accelerates uniformly with an angular acceleration of 4rad/〖sec〗^2. What will be its angular velocity after 4 seconds and the total distance traveled in that time?
Homework Equations
The Attempt at a Solution
i have got my answer...
Homework Statement
A flywheel takes 5 seconds to rotate through 5 revolutions starting from rest. If it is accelerating at a constant rate during that time, what is the angular acceleration?
Homework Equations
∅=ω t+at^2
The Attempt at a Solution
having done my calculations i...
Homework Statement
Determine the maximum speed at which a vehicle can negotiate a curve of
20m radius:
The vehicle has a track width of 1.3m and a centre of gravity midway between the wheels and 0.6m above the ground. The coefficient of friction between the tyres and the road is 0.5...
Homework Statement
Calculate the maximum speed with which a vehicle can travel round a horizontal bend of radius 40m without skidding if the coefficient of friction between the tyres and the road is 0.6.
Homework Equations
v=sqrt μrg
The Attempt at a Solution
v=sqrt 0.6 x 40m x...
Last spring, I wrote on one of my blogs about an idea regarding the looping, underhand pitching motion in women's college softball. The idea is that tall, long-armed pitchers may derive greater velocity on their pitches than would shorter pitchers with shorter arms (overall body height and arm...
We have linear & angular velocities related by:
v=r.omega.
&
a=r.alpha
On my textbook it's said" Above two equations show that on a rotating body,points that're at different distances from the axis do not have the same speed or acceleration,but all points on a rigid body rotating about a...
okay, I've thought about this for a while and still can't figure it out and its absolutely bugging me to death
here's the picture:
http://img307.imageshack.us/img307/3193/problemcr4.gif
Assume that the static friction coefficient between the cylinder and the ground is "u", the gravitational...
Hey, I have this question here, the hardest one on this sheet, and I've been stuck on it all day now. I'd really appreciate maybe just a hint, as I want to do it myself but I just need a kickstart.
I drew three free body diagrams for each position of the pendulum, then marked off tension and...
Suppose the Earth is a perfect sphere with R = 6370 KM. If a person weighs exactly 600 N at the north pole, how much will the person weigh at the equator.? (Hint: The upward push of hte scale on the person is what the scale will read and is what we aer calling the weight in this case)
ANS...
The human body can safely stand an acceleration 9 times that due to gravity. With what minimum radius of curvature may a pilot sfely turn the plane upward at the end of a dive if the plane's speed is 770km/h.
i did a quesotin before this, which had a roller coaster
i did mgh at a = 1/2 mv...
Hi.
I have two questions which I have been pondering on and I just can't figure it out. Maybe someone could be kind enough to answer the questions?
Q1; Projectile motion: Let's say we dropped a ball from a height called h.
We achieve a velocity v=\sqrt{2gh} . Let's then say that we hit...
A stick of uniform density with mass M = 7.6 kg and length L = 0.8 m is pivoted about an axle which is perpendicular to its length and located 0.13 m from one end. Ignore any friction between the stick and the axle...
2 questions, that I just can't get and anyone's help would be greatly appreciated...
A belt runs on a wheel of radius 44cm. During the time the wheel takes to coast uniformly to rest from an initial speed of 1.8 rev/s, 29.5m of belt length passes over the wheel. Find:
(a) the deceleration...