Homework Statement
A student ties a 500 g rock to a 1.0-m-long string and swings it around her head in a horizontal circle.
At what angular velocity in rpm does the string tilt down at a 16 degree angle?
Homework Equations
F = (m*v^2)/r
v = r*w
The Attempt at a Solution
[/B]
First I solved...
Homework Statement
A child swings a tennis ball attached to a .750 m-string in a horizontal circle above his head at a rate of 5.00 rev/s What is the centripetal acceleration of the tennis ball?
Homework Equations
angular speed \omega = 2pi/T
speed = r\omega
a_c = -v^2 /r
a_c = -\omega ^2...
I'm trying to understand the geometrical meaning of acceleration in circular motion. When I consider a particle moving in a circular path, I can clearly see that the acceleration vector can be composed of a tangential and radial component. But since the change in velocity happens over a period...
Homework Statement
A ball with radius ##r## is inside a hollow cylinder with radius ##r+R##.
In the first part of the assignment, one has to calculate the minimum kinetic energy the ball has to have at the bottom in order to complete a full loop in the cylinder. It turns out to be...
This question came to mind from the thread...
https://www.physicsforums.com/threads/can-a-photon-be-accelerated.901484/
Knowing...
1) Strong gravitational fields create strong curves in spacetime
2) Light traveling through strong gravitational fields get curved along the spacetime
3)...
Homework Statement
A uniform thin circular rubber band of mass M and spring constant k has an original radius R. Now it is tossed into the air. Assume it remains circular when stabilized in air and rotates at angular speed ω about its center uniformly. Derive an expression for the new radius...
Homework Statement
Hi,
If an object is undergoing uniform circular motion, then the net force is acting perpendicular to the instantaneous velocity, and this is called the centripetal force.
However, if the object is moving in a circle but the magnitude of its instantaneous velocity is not...
Homework Statement
Hi, I was wondering what is the difference between the equations an=w^2 x R vs an=V^2 / R? I thought both of these equations were the same? What is the normal acceleration at C and D?
Homework Equations
an=w^2 x R vs an=V^2 / R?
The Attempt at a Solution
[/B]
If I use...
Recently, I was looking into centripetal acceleration and there's something I don't understand.
According to my book, during uniform circular motion, the acceleration is
a= v^2/r
where v is the speed at which the object is moving and r is the radius of the circle.
However, this formula is...
Ok, so I'm a bit confused by the derivation of a=v^2/r in Feynman's "Six Not-So-Easy Pieces".
In pages 17-18, it is stated that "The other component of acceleration, at right angles to the curve, is easy to calculate, using Figures 1-7 and 1-8. In the short time Δt let the change in angle...
Homework Statement
An object is in uniform circular horizontal motion at the end of a chord of length L. Its tangential speed is v. The chord is pulled into length 0.5L in such a way that the tension in the chord remains constant. As a result, the tangential speed:
a) remains constant
b)...
Homework Statement
The right answer is E, and I have no idea how to solve this problem.
Please advise on how to proceed. Thanks in advance.
Homework Equations
conservation of mechanical energy??
The Attempt at a Solution
Many attempts were done, but I am lacking on theory with this. How...
Homework Statement
Homework Equations
I know that Fc = m * centripetal acceleration, where the Fc = the force of gravity
The Attempt at a Solution
[/B]
I was able to use process of elimination to get B for 25 correctly, but I am not able to understand how it is the right answer.
How can...
Hello,
This is a very basic question. I am sure I am doing something wrong in the derivation as shown in the picture. But I am not able to find out where I am doing it wrong. It would be very helpful if you can pls. let me know what I am doing wrong here.
Thanks
Homework Statement
Imagine another planet with an acceleration of 10.00 m/s^2 at its equator when ignoring the rotation of the planet. The radius is 6.2 x10^6 m. An object dropped at the equator yields an acceleration of 9.70 m/s^2. Determine the length of 1 day on this planet.
Homework...
Homework Statement
the centripetal acceleration of an object at Earth's equator results from the daily rotation of Earth. Calculate the object's centripetal acceleration, given that the radius of Earth at the equator is 6.38*10^6m.
Homework Equations
a=v^2/r
The Attempt at a Solution
I really...
Homework Statement
The picture has the problem question.
OK.
When the moon is at point B, the distance from the moon to the center of the planet is most nearly:
A) (1/25) * rA
B) (1/5) * rA
C) (1/ sqrt(5) ) * rA
D) rA
E) sqrt(5) * rA.
Homework Equations
Newton's law of gravitation...
Im picturing a stationary object at the equator of the earth, going around in uniform circular motion due to the Earth's rotation. The centripetal acceleration would point directly inwards into the Earth at all points in the circular rotation, and gravity would also point in the same direction...
Just using basic dimensional analysis, it appears the time derivative of centripetal acceleration is ## \vec{r} \omega^3 ##, but this intuitive guess would also extend to higher order time derivatives, no? Implying:
## \frac {d^n \vec{r}}{dt^n} = \vec{r} \omega^n ##
It seems to follow from the...
Homework Statement
In a certain carnival ride, visitors enter a circular room with radius r=9.1m. The room then begins spinning around its center, reaching an angular speed of 1.7rad/s. What centripetal acceleration do the riders experience?
Homework Equations
ac= v^2/r
The Attempt at a...
How can you calculate centripetal acceleration in a non circular system(I.E. if wanted to calculate the centripetal acceleration in an eclipse, or a parabola how could I do that?)
Homework Statement
A block of mass 2kg (mb) can slide down a frictionless 53 degree inclune, but it is connected to a pulley of mass 4kg (mp with a radius of 0.5m. The pulley may be treated as a disk.
What is the angular acceleration of the pulley?
Homework Equations
a = rα
The Attempt at a...
Homework Statement
Have platform A that is being spun by a centrifuge with a radius R1 and centripetal velocity of w1. On top of platform A is a Lazy Susan (Platform B) that spins about a radius R2 with a centripetal velocity of w2. There are accelerometers placed on the the purple platform...
It can be found in any advanced calculus textbook the proof that, for a "well-behaved" space curve, the acceleration vector can be decomposed into components along the tangent and normal unit vectors. The acceleration vector is always orthogonal to the binormal vector.
The decomposition is...
Homework Statement
[/B]
Everywhere I looked they solved this problem with energy conservation, but is it possible to solve it using centripetal acceleration?
Homework Equations
The Attempt at a Solution
I tried putting (mv^2/r)*sin (theta) - F= ma which i solved for a. This gives me...
Homework Statement
Tarzan plans to cross a gorge by swinging in an arc from a hanging vine. If his arms are capable of exerting 1350 N on the vine, what is his acceleration at the point where the vine makes an angle of 45 degrees from the vertical assuming maximum speed at this point. His mass...
Homework Statement
For a scene in a movie, a stunt driver drives a 1.20✕ 103 kg pickup truck with a length of 4.65 m around a circular curve with a radius of curvature of 0.333 km (Fig. 7.29). The truck is to curve off the road, jump across a gully 10.0 m wide, and land on the other side 2.96 m...
Homework Statement
At the Olympic bob-sleigh competition, a new (I admit, fairly boring...) track
has been built, as drawn in the figure. It is composed of straight lines with
lengths as indicated in the figure and 90.0 degree turns, each with the same
radius of curvature r1 = r2 = r3 = r4...
Homework Statement
Two protein having same density 1.35 g /cm^3 but with different diameter 4nm and 5nm. They are mixed at the top of a centrifuge tube that is of length 1cm. What is the centripetal acceleration needed to separate them before they move to the end of the tube?
Homework...
I know that the centripetal force is the resultant force which points to the center. So in the case of a washing machine, what force pushes the clothes and water to the outer edge? There is not centrifugal force, but then how come all the clothes appear to get pushed to the circumference of the...
Homework Statement
A skateboarder has to do a loop the vertical loop of a roller coaster track. The radius of the loop is 6.53 m, what is the minimum velocity the skateboarder must have to not fall off when he is at the top of the loop.
Homework Equations
Equation for centripetal...
Homework Statement
i was going through uniform circular but a confusion popped out of my head .
as i have read before the Rutherford atomic model was only rejected due to
the fact that electrons moving in circular orbits need to accelerate constantly
to maintain a uniform speed but the...
Homework Statement
A small container of water is placed on a turntable
inside a microwave oven, at a radius of 12.0 cm from
the center. The turntable rotates steadily, turning one
revolution in each 7.25 s. What angle does the water
surface make with the horizontal?
Homework Equations
F = ma
a...
A comparison of corresponding parts of these two similar isosceles triangles yields
velocity triangle
displacement triangle
where
|-vo| = |vf| = v
In a small time interval Δt, the arc length s → c.
Okay, so I got this from Physics LAB, and I don't understand the last statement that...
Why is there no component of tangential acceleration in uniform circular motion? I think its because when we apply the WE Theorem (Work-Energy Theorem) as follows:
Work Done = ΔKE
=> F.S = 1/2*m*(vf2 - vi2),
=>(ma).s = 1/2*m*(vf2 - vi2)
=> (ma).s = 1/2*m*(0) (since the speed remains constant in...
Homework Statement
I also need help on a problem. but FIRST, can someone explain to me how radial acceleration relates to gravity and how gravity can be split up into tangential and radial accelerations and how that can be compared to radial acceleration ? I know the basic stuff..like if a...
Hi guys...
So i searched the net for 2 whole days and found a couple of topics on how static friction is responsible for creating the force required to keep the body moving in a circle.. Friction points towards the center of the circle ONLY when the car is free wheeling i.e moving at a constant...
1) Problem Statement:
A car travels forward with constant velocity. It goes over a small stone, which gets stuck in the groove of a tire. The initial acceleration of the stone, as it leaves the surface of the road, is
(A) vertically upward
(B) horizontally forward
(C) horizontally backward
(D)...
Hi. I have a question that I can't seem to figure out in my self study of physics. Why does centripetal acceleration point inward?
When I drive around a corner, my body experiences a push away from the corner. I go that way, however, because of the car pushing me towards it. Not because of the...
Homework Statement : A centrifuge starts from rest and speeds up at 3400rpm after 50 seconds.
a sample is at a distance of 37.5mm from the centre
1) find the angular acceleration
2) calculate the centripetal acceleration [/B]
Homework Equations :
v2 / r
v = rω
a = rω2
a=Λω/Λt
3. The...
Since F=mv2/r. Does that mean the force required for centripetal acceleration is inversely proportional to the radius? If radius is more the lesser centripetal force is required, is this correct?
first of all thanks for reading and especially thank you to people who helped with my previous question here https://www.physicsforums.com/threads/does-the-coefficient-of-friction-change-with-the-angle.798572/#post-5019349
Unfortunately i am having more problems with this instructor insisting...
Homework Statement
Q.1. Explain the changes in the tension of a piece of string which is being swung vertically with a bucket of water at the end. What would the minimum centripetal acceleration need to be for water to not fall out?Homework Equations
ac = v^2/r
The Attempt at a Solution
The...
Homework Statement
A rocket car is constrained to move on an elliptical track (semi-major axis a and semi-minor axis b ). The car is moving at a constant speed v_0 . Determine the acceleration of the car in \frac{m}{s^2} . a = 4 \hspace{2 mm} km , b = 2 \hspace{2 mm} km , and v_0 = 360...
Homework Statement
An airplane flies in a loop (a circular path in a vertical plane) of radius 120m . The pilot's head always points toward the center of the loop. The speed of the airplane is not constant; the airplane goes slowest at the top of the loop and fastest at the bottom.
At the top...
How Can I Prove this Physically
Homework Statement
[/B]
So I need to do a project where I prove centripetal acceleration. All the cases I've seen of where it's proved is using formulas, though I need an actual project.
By an actual project I mean something like...
Hi all,
If anything here is incorrect or confusing or seems trivially simple, I apologize: I'm not a physicist and created an account specifically to get help on this from some people who are!
My question is this:
Assume a plane has a constant airspeed and you wish to fly a circular pattern...
Hi all. The answer to this might be trivial. If it is, sorry for posting. If you calculate the acceleration due to gravity of an orbiting satellite, it could be around 8.5-9.5m.s-2, depending. So, it's tangential velocity is such that as it falls towards earth, Earth curves away and the...
Homework Statement
A roller coaster is on a track that forms a circular loop in the vertical plane. If the car is to just maintain contact at the top of the loop, what is the minimum value for its centripetal acceleration at this point?
A) 2g downward
B) g downward
C) 2g upward
D) g upward
E)...
< Mentor Note -- Thread moved from the General Physics forum to HH >
A ball swings counterclockwise in a vertical circle at the end of a rope 1.50 m long. When the ball is 36.9 degrees past the lowest point on its way up, its total acceleration is (-22.5i + 20.2j) m/s^2. For that instant, (a)...