Homework Statement
A cat rides a merry-go-round turning with uniform circular motion. At time t1 = 2.00 s, the cat’s velocity is V1 = (3.00 m/s)i + (4.00 m/s)j , measured on a horizontal xy coordinate system. At t2 = 5.00 s, the cat’s velocity is V2 = (3.00 m/s)i + (4.00 m/s)j.
What are (a) the...
Homework Statement
A car drives along a curved track. The frictional force exerted by the track on the car is:
a. greater than the frictional force exerted by the car on the track
b. directed radially outward
c. opposite in direction to the frictional force exerted by the car on the track
d...
Hello,
I am curious to see how the mathematical analysis of a vertical circular motion with a sensible rope, that is to say, a rope that streches easily, looks like. k- constant of the rope.
thanks,
Homework Statement
Its a classic problem about a puck that is rotating on a frictionless tabble with a velocity v1 and radius r1. It is is connected to a string which runs through a hole a the centre of the table. The string is pulled from below until the radius decreases to r2. Find the work...
If a smooth sphere with radius a is fixed on a plane, and a particle is projected horizontally at the highest point outside/on of the sphere with speed (4ag/5)^0.5, I know that the particle will lose contact with the sphere when it makes an angle of theta with the upward vertical, where theta is...
Homework Statement
A ball rolls down a ramp which forms a quarter circle of radius 0.5m. The ball weighs 25g. The bottom of the ramp is 1.5m above the floor. Assume no friction between the ball and the ramp. Assume no air resistance.
what is the force exerted by the ramp on the ball?
whatis...
There is a problem in my Physics textbook which says:
Homework Statement
"A car runs counter-clockwise in a circular lane of 1 km of diameter, going through the south extreme at 60 km/h on the instant t = 0. From that point onwards, the driver accelerates the car uniformely, reaching 240 km/h...
Homework Statement
A 1.5 kg ball is tied to a string that is .75 m long and whirled in a verticle circle.
A) Find the tension in the string at the top of the circle
B) Find the tension in the string at the bottom of the circle
Homework Equations
Fc=mac
ac= v2/r
The Attempt at a Solution
A)...
Imagine we take a vertical, infinite wire and we let electric current pass through. The charges create magnetic field all around the wire.
Now if we introduce an electron in the magnetic field, it will have a circular motion around the wire. The Lorentz force is not conservative, this means...
Hi, if you consider a ball, with mass m, rolling down the outer surface of a hemisphere with radius r, why is it that if you consider the forces acting upon the ball and resolve in a direction, the equation formed is:
mgcos(x) - R = m(v^2)/r
If you rearrange that, it would appear that the...
Homework Statement
A heavy mass m is attached to thin wire and whirled in a vertical circle. Then the wire is most likely to break
A only when mass is at the lowest
B somewhere between lowest point and horizontal point
C only when mass is horizontal
D only when mass is at highest point...
Homework Statement
The pre-lab is based on the following lab: http://iws.collin.edu/mbrooks/physics/experiments/PHYS 2425 Exp 7 Manual.pdf
Moderator edit: Extract of an image from the PDF showing the mechanism under discussion:
1. Draw two free-body diagrams for the rotating mass in teh...
Homework Statement
An object with mass of m traveling in a circle rail ,when reached point A the object derailed and moved in a parabola path to point B and so on find the length of AB in term of R and theta. given that B is on the same horizontal level as A
Homework EquationsThe...
Homework Statement
A particle of mass m is moving on a frictionless horizontal table and is attached to a massless string that passes through a tiny hole of negligible radius in the table, and I am holding the other end of the string underneath the table. Initially the particle is moving in a...
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 biker is 40.0m to the east of a flag in a park, heading south at 10m/s. 30.0 seconds later, the biker is 40.0m north of the flag and heading east at 10.0m/s. For the biker in this 30.0s interval, what are:
a) the magnitude and direction of the displacement?
b) the magnitude...
1. Homework Statement
An amusement park ride consists of a large vertical cylinder that spins about its axis fast enough that any person inside is held up against the wall when the floor drops away (see figure). The coefficient of static friction between person and wall is μs, and the radius of...
Homework Statement
in circular motion (e.g. a pendulum) is the kinetic energy still 1/2 m v ^2 or is it a different equation?
Homework Equations
1/2 m v ^2
The Attempt at a Solution
1- I am trying to understand the rotational motion and In most books there's ##\vec θ## unit vector which its, ##\vec θ=(-sinθ,cosθ)##
I can see that If ##\vec r## unit vector is,##\vec r=(cosθ,sinθ)## then ,
##\frac {d\vec r} {dt}=\vec θ##
Like calculating ##\vec v=\frac {d\vec r}...
Homework Statement
An aircraft flies with its wings tilted, in order to fly in a horizontal circle of radius r. The aircraft has mass 4.00 x 104 Kg and has a constant speed of 250ms-1 . with the aircraft flying in this way, two forces are acting on the plane, P [lift] and W [weight which is...
Homework Statement
Homework Equations
F = mw^2r
[/B]The Attempt at a Solution
For part a, I can't get the constant of half with the tan a
I am getting tan a = w^2l/g
Hello
I am a little confused by the following problem: Mass in cone: A particle of mass m slides without friction on the inside of a cone. The axis of the cone is vertical, and gravity is directed downward. The apex half-angle of the cone is θ, as shown. The path of the particle happens to be a...
I often hear inertia used as an explanation in areas where it seems to make intuitive sense, but appears to me to be inconsistent with the definition of inertia as just depending on an object's mass. I offer three examples (they're very similar):
Example 1: An elevator
Suppose an elevator...
Homework Statement
Homework EquationsThe Attempt at a Solution
Why can't we take the moment on the left wheel?
In this case,
2d(N2) - mgd
= mgd + m(v^2)h/r - mgd
=m(v^2)h/r ≠ 0
Shouldn't there be an anticlockwise moment about the left wheel?
Homework Statement
Jessie (m=56.2 kg) is traveling at a speed of 12.8 m/s at the top of a 19.5-m high roller coaster loop.
a) Assuming negligible losses of energy due to friction and air resistance, determine Jessie's total mechanical energy at the bottom of the loop (h=0 m). (ans: 1.53 x 104...
Homework Statement
A train engine of mass ##m## is chugging its way around a circular curve of radius ##R## at a constant speed ##v##. Draw a free body/force diagram for the train engine showing all of the forces acting on it.
Evaluate the total vector force acting on the engine as a function...
Homework Statement
http://[URL=http://www.siz.co.il/][PLAIN]http://up416.siz.co.il/up3/w2jymjm5nqxy.png [/B]
A body with a mass that equals to m is inside a smooth tube and is attached to two identical springs with constants that equal to k. Their length when they are limp is L0. When the...
Homework Statement
[/B]
I need to help solving part a)
Homework Equations
[/B]
$$v= \frac{2\pi}{T}$$
$$(\frac{T_1}{T_2})^2 = (\frac{r_1}{r_2})^3$$
The Attempt at a Solution
I'm not sure where to begin really. One approach I tried was getting T_1 in terms of v_0 and plugging it into...
Homework Statement
Homework EquationsThe Attempt at a Solution
I am actually stumped by this seemingly simple problem . Since both the particles are moving , in order to calculate angular velocity of Q with respect to P looks to be difficult as the relative velocity of Q w.r.t P is...
Homework Statement
A car moves from X to Y along a semicircular path. The radius of the path is 250 m and the time taken to complete the trip is 50 s.
What is the magnitude of the average velocity and the magnitude of the average speed?
can you please explain? <3
Homework Equations
v = wr = 2π...
1.
2.
Well, these are two pics on circular motion, i found on net...
If the objects had a zero rotational motion before circular motion, and the next moment suddenly a force acts ( perpendicular to their linear momentum ) such that they move in circular motion,... which of these pictures...
Homework Statement
A ball of mass m is attached to a rope of length L which has one end at the origin; the ball moves in a horizontal circle at constant speed v0 on a frictionless plane; the velocity is always at 90◦ to the rope. The ball has a charge q, and moves in a constant magnetic field...
Homework Statement
In the case of circular motion,the direction of the velocity is changing in every moment.So,there is a angular accelleration here.What is the direction of this accelleration?
Homework EquationsThe Attempt at a Solution
Homework Statement
A particle starting from rest revolves with uniformly increasing speed in a clockwise circle in an xy plane. The center of the circle is at the origin of an xy coordinate system. At t=0, the particle is at x=0.0m, y=2.0m. At t=2.0s, it has made one-quarter of a revolution and...
I've been thinking about centripetal force and circular motion. I know that an object experiencing circular motion has a velocity vector tangential to the circular path and an acceleration vector perpendicular to its motion, pointing towards the center of the circle.
What I don't get is why...
Homework Statement
A pendulum traveling at constant speed along a circular path
Determine the angle that the string makes with the vertical.
T[/B]he length of the string was measured to be 60 cm.
The period was measured to be 1.41 s
The frequency was found to be 0.709
2. Homework Equations...
Homework Statement
Our teacher gave us a formula to solve it by creating a computer program but the problem is I'm not good at physics. I need to know what is Fc,Mr,Fk etc..
1.) Fc = Mr(theta - Oo) ^ 2 / (t - tn) ^ 2
2.) M = Fk / Mk(m)(g)cos(theta)
Homework EquationsThe Attempt at a...
Homework Statement
A hockey puck with mass 200 g is attached to a rope of length 62.0 cm and swung in a horizontal circle against the ice at a rate of 58.0 rpm. Assuming the ice is frictionless, what is the tension in the rope?
Homework Equations
FT = mω2r
The Attempt at a Solution
58rpm =...
Hello! I am just stuck on one part of this question and would be grateful for any help.
Question
A small block of ice slides from rest from the top of an inverted frictionless bowl of radius
R (above right). How far below the top x does the ice lose contact with the bowl?
Equations
mgx =...
In the figure below we put a small coin on a disc, which rotates at constant frequency f, at a distance D=0.2m by the disc rotation axis. If the coefficient of friction is μ=0.5, then what is is the maximum frequency that can have the disc so that the currency does not slip? g=10 m/sec^2
Anyone...
Homework Statement
A stone tied to a string with length 1.10 m is whirled in a circle both horizontally and vertically with the same constant speed. In the vertical case the maximum tension in the string is 15.0% larger than the tension that exists when the string was horizontal. Determine the...
Homework Statement
1. A car is safely negotiating an unbanked circular turn at 21 m/s and the maximum static force acts on the tires. Suddenly a wet patch on the road reduces the static frictional force by a factor of three. At what speed must the driver slow to in order to safely continue on...
Homework Statement
A small ball with mass m=1.1kg moves on the end of a string with length L=2.9. The string is anchored at point A and travels in a horizontal circle as shown. The string is at and angle of 36 degrees from the vertical.
What is the string tension as the ball swings in this...
Homework Statement
A particle of mass ##m## moves along a circle of radius ##R##. The modulus of the average vector of the force acting on the particle over the distance equal to a quarter of the circle is:
zero if the particle moves with uniform speed ##v##.
##\dfrac{\sqrt2mv^2}{\pi R}## if...
Homework Statement
"Figure 8-32 shows a pendulum of length ##L=\frac{5}{4}m##. Its bob (which effectively has all the mass) has speed ##v_0## when the cord makes an angle ##\theta_0=40°## with the vertical. (a) What is the speed of the bob when it is in its lowest position if...
I am curious as to the formula for radiative power due to a single object in forced circular motion.
In particular, I am interested in the power of gravitational radiation for volumetric invariant mass densities for both the low density Newtonian limit and the high density general relativistic...
Homework Statement
An object of mass 0.8kg is whirled round in a horizontal circle of radius 2m with a constant speed of 15ms-1. Calculate the tension in the string.
The Attempt at a Solution
So far I have calculated that the angular velocity is 7.5rads-1, the frequency is 1.19Hz and the time...
[moderator's note: Thread moved from forum General Physics, so no template shown]
The angular velocity of a process control motor is (10−1/2t^2) rad/s, where t is in seconds.
a. At what time does the motor reverse direction?
I got 4.5 s which is correct
b. Through what angle does the motor...