Question

In: Advanced Math

The merry-go-round rotates counterclockwise with a constant angular speed u. The distance between the horse on...

The merry-go-round rotates counterclockwise with a constant angular speed u. The distance between the horse on the merry-go-round and the rotational center is r.

(a) Find the position of the horse x and its velocity v, v(t) = d/dt x(t), as vector-functions of time.


(b) Find the acceleration of the horse, a(t) = d^2/dt^2 x(t), as a vector-function of time. What is its direction (in comparison with the direction of x)?

Now the same horse has a non-constant angular speed u(t) (the merry-go- round still rotates counterclockwise).

(c) Find the position of the horse x and its velocity v, v(t) = d/dt x(t), as functions of time.


(d) Find the acceleration of the horse, a(t) = d^2/dt^2 x(t), as a function of time.

(e) What is the direction of a(t) at the moment when the merry-go-round starts to rotate?

Solutions

Expert Solution


Related Solutions

A disk-shaped merry-go-round of radius 2.63 m and mass 155 kg rotates freely with an angular...
A disk-shaped merry-go-round of radius 2.63 m and mass 155 kg rotates freely with an angular speed of 0.570 rev/s. A 59.4-kg person running tangential to the rim of the merry-go-round at 3.82 m/s jumps onto its rim and holds on. Before jumping on the merry-go-round, the person was moving in the same direction as the merry-go-round's rim. (a) Does the kinetic energy of the system increase, decrease, or stay the same when the person jumps on the merry-go-round? (b)...
Suppose a child gets off a rotating merry-go-round. Does the angular velocity of the merry-go-round increase,...
Suppose a child gets off a rotating merry-go-round. Does the angular velocity of the merry-go-round increase, decrease, or remain the same if: (a) He jumps off radially? (b) He jumps backward to land motionless? (c) He jumps straight up and hangs onto an overhead tree branch? (d) He jumps off forward, tangential to the edge?
A wheel rotates with a constant angular acceleration of 3.0 rad/. If the angular speed of...
A wheel rotates with a constant angular acceleration of 3.0 rad/. If the angular speed of the wheel is 2 rad/s at t = 0, through what angular displacement does the wheel rotate in 2 s? 10 rad. 6 rad. 15 rad. 4 rad. 12 rad. Based on question number 3, through how many revolutions has the wheel turned during this time interval?   4 rev. 3 rev. 1.6 rev. 5 rev. 2 rev. Based on question number 3, what is...
A disk rotates with constant angular acceleration. The initial angular speed of the disk is 2?...
A disk rotates with constant angular acceleration. The initial angular speed of the disk is 2? rad/s. After the disk rotates through 20? radians, the angular speed is 3? rad/s. (a) What is the magnitude of the angular acceleration? rad/s2 (b) How much time did it take for the disk to rotate through 20? radians? s (c) What is the tangential acceleration of a point located at a distance of 3 cm from the center of the disk? m/s2
Rod OA rotates counterclockwise with a constant angular velocity of = 5 rad/s. The double collar...
Rod OA rotates counterclockwise with a constant angular velocity of = 5 rad/s. The double collar B is pin connected together such that one collar slides over the rotating rod and the other slides over the horizontal curved rod, of which the shape is described by the equation r = 1.5(2 - cos θ) ft. If both collars weigh 0.75 lb, determine the normal force which the curved rod exerts on one collar at the instant θ = 120o. Neglect...
A helicopter has a rotor (radius R0) that rotates with constant angular speed ω. The helicopter...
A helicopter has a rotor (radius R0) that rotates with constant angular speed ω. The helicopter is accelerating vertically with constant acceleration A0, starting from rest. Using cylindrical coordinates a) Write the position vector of the tip of the rotor as a function of time. b) Find the velocity vector of the rotor tip as a function of time by taking the derivative of the previous result. c) Find the acceleration vector of the rotor tip as a function of...
Consider the child's playground merry-go-round wheel. Merry Go Round If the steel disk has mass of...
Consider the child's playground merry-go-round wheel. Merry Go Round If the steel disk has mass of 200 kg and a radius of 2 meters you can make it spin by applying a force to the rim. This torque increases the angular momentum of the disk. Suppose the force is 20 newtons. How long would you have to apply it to get the wheel spinning 5 times a minute? What would happen to the rate of spin if you then jumped...
A playground merry-go-round has a disk-shaped platform that rotates with negligible friction about a vertical axis....
A playground merry-go-round has a disk-shaped platform that rotates with negligible friction about a vertical axis. The disk has a mass of 200 kg and a radius of 1.6 m. A 34- kg child rides at the center of the merry-go-round while a playmate sets it turning at 0.15rpm. If the child then walks along a radius to the outer edge of the disk, how fast will the disk be turning? (in rpm - but enter no unit)
Bubba (m=100kg) and Sally (m=60kg) are playing on a merry-go-round. Treat the merry-go-round as a disk...
Bubba (m=100kg) and Sally (m=60kg) are playing on a merry-go-round. Treat the merry-go-round as a disk with mass 100 kg and radius 1.3 m. Both Bubba and Salley are at the edge of the disk when the disk is rotating at .25 revolutions per second. Suppse Bubba moves inward so that he is now exactly at the center. Treat the two children as point masses. Assuming there is no external torques or forces, A) What is the new rotational speed...
A merry-go-round is a common piece of playground equipment. A 3.0-mm-diameter merry-go-round, which can be modeled...
A merry-go-round is a common piece of playground equipment. A 3.0-mm-diameter merry-go-round, which can be modeled as a disk with a mass of 220 kg, is spinning at 24 rpm. John runs tangent to the merry-go-round at 5.6 m/s, in the same direction that it is turning, and jumps onto the outer edge. John's mass is 30 kg.
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT