A sphere of radius \(R\) and mass \(M\) sits on a horizontal tabletop. A horizontally directed impulse with magnitude \(J\) is delivered to a spot on the ball a vertical distance \(h\) above the tabletop. a) Determine the angular and translational velocity of the sphere just after the impulse is delivered. b) Determine the distance \(h_{0}\) at which the delivered impulse causes the ball to immediately roll without slipping.

Short Answer

Expert verified
Question: Determine the angular and translational velocities of the sphere just after the impulse is delivered and the distance at which the impulse causes the ball to roll without slipping instantly. Answer: The angular and translational velocities of the sphere just after the impulse are given by \(v_{f} = \frac{J}{M}\) and \(\omega_{f} =\frac{J\cdot h}{\frac{2}{5}MR^2}\). The distance at which the delivered impulse causes the ball to immediately roll without slipping is \(h_{0} =\frac{2}{5}R\).

Step by step solution

01

Identify the given values

The problem provides us with the following information: - Sphere radius: R - Sphere mass: M - Impulse magnitude: J - Vertical distance above the tabletop: h
02

Determine the linear impulse delivered

Impulse-momentum theorem states that the impulse applied equals the change in linear momentum. The linear momentum is given by the product of the mass and velocity. Let's denote the linear impulse as J_lin. Since the sphere is initially at rest, the change in linear momentum is equal to the final linear momentum, \[J_{lin} = Mv_{f}\] We need to solve for the final linear velocity, \(v_{f}\), so we divide by the mass M, \[v_{f} = \frac{J_{lin}}{M}\]
03

Determine the angular impulse delivered

Angular momentum is the product of the moment of inertia (I) of the sphere and its angular velocity (ω). The moment of inertia of a sphere is given by \[I = \frac{2}{5}MR^2\] For the impulse J applied at a distance h from the center, we can determine the angular impulse by considering the torque (τ) caused by the impulse. The torque is the product of the perpendicular distance and the force. Let's denote the angular impulse as J_ang. Since the sphere is initially at rest, the change in angular momentum is equal to the final angular momentum, \[J_{ang}=I\omega_{f}\] We need to find the final angular velocity (\(\omega_{f}\)) so we divide by moment of inertia, \[\omega_{f} = \frac{J_{ang}}{I} = \frac{J_{ang}} {\frac{2}{5}MR^2}\]
04

Obtain the angular and translational velocities

Now, we can substitute the angular and translational impulses (J_ang and J_lin, respectively) with the given impulse J. For the linear impulse, since it is applied horizontally, it is equal to the given impulse J, so \[v_{f} = \frac{J}{M}\] For the angular impulse, it is given by the product of the applied impulse (J) and the perpendicular distance (h) from the center, \[\omega_{f} =\frac{J \cdot h}{I}=\frac{J\cdot h}{\frac{2}{5}MR^2}\] #b) Distance h0 for rolling without slipping#
05

Define a rolling condition without slipping

For a sphere to roll without slipping, its linear velocity and angular velocity should be related by the equation, \[v_{f} = R\omega_{f}\]
06

Replace vf and ωf with the expressions found in part a)

Now, we substitute the expressions we found for the linear and angular velocity above, \[\frac{J}{M} = R\left(\frac{J\cdot h_{0}}{\frac{2}{5}MR^2}\right)\]
07

Solve for h0

In this step, we will solve the equation for \(h_{0}\). First, we can simplify the equation by canceling out J and dividing by R: \[\frac{1}{M} = \frac{h_{0}}{\frac{2}{5}MR}\] Now, we solve for \(h_{0}\), \[h_{0} = \frac{2}{5}MR\cdot\frac{1}{M}=\frac{2}{5}R\] Upon solving the problem, we found that the angular and translational velocities of the sphere just after the impulse are given by: \[v_{f} = \frac{J}{M}\] and \[\omega_{f} =\frac{J\cdot h}{\frac{2}{5}MR^2}\] We also found that the distance \(h_{0}\) at which the delivered impulse causes the ball to immediately roll without slipping is: \[h_{0} =\frac{2}{5}R\]

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

A uniform solid cylinder of mass \(M=5.00 \mathrm{~kg}\) is rolling without slipping along a horizontal surface. The velocity of its center of mass is \(30.0 \mathrm{~m} / \mathrm{s}\). Calculate its energy.

In a tire-throwing competition, a man holding a \(23.5-\mathrm{kg}\) car tire quickly swings the tire through three full turns and releases it, much like a discus thrower. The tire starts from rest and is then accelerated in a circular path. The orbital radius \(r\) for the tire's center of mass is \(1.10 \mathrm{~m},\) and the path is horizontal to the ground. The figure shows a top view of the tire's circular path, and the dot at the center marks the rotation axis. The man applies a constant torque of \(20.0 \mathrm{~N} \mathrm{~m}\) to accelerate the tire at a constant angular acceleration. Assume that all of the tire's mass is at a radius \(R=0.35 \mathrm{~m}\) from its center. a) What is the time, \(t_{\text {throw }}\) required for the tire to complete three full revolutions? b) What is the final linear speed of the tire's center of mass (after three full revolutions)? c) If, instead of assuming that all of the mass of the tire is at a distance \(0.35 \mathrm{~m}\) from its center, you treat the tire as a hollow disk of inner radius \(0.30 \mathrm{~m}\) and outer radius \(0.40 \mathrm{~m}\), how does this change your answers to parts (a) and (b)?

A solid sphere rolls without slipping down an incline, starting from rest. At the same time, a box starts from rest at the same altitude and slides down the same incline, with negligible friction. Which object arrives at the bottom first? a) The solid sphere arrives first. b) The box arrives first. c) Both arrive at the same time. d) It is impossible to determine.

A 0.050 -kg bead slides on a wire bent into a circle of radius \(0.40 \mathrm{~m}\). You pluck the bead with a force tangent to the circle. What force is needed to give the bead an angular acceleration of \(6.0 \mathrm{rad} / \mathrm{s}^{2} ?\)

A machine part is made from a uniform solid disk of radius \(R\) and mass \(M\). A hole of radius \(R / 2\) is drilled into the disk, with the center of the hole at a distance \(R / 2\) from the center of the disk (the diameter of the hole spans from the center of the disk to its outer edge). What is the moment of inertia of this machine part about the center of the disk in terms of \(R\) and \(M ?\)

See all solutions

Recommended explanations on Physics Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free