SP1. A merry-go-round in the park has a radius of 1.8 m and a rotational inertia of 900 kg-m². A child pushes the merry- go-round with a constant force of 80 N applied at the edge and parallel to the edge. A frictional torque of 12 N-m acts at the axle of the merry-go-round. a. What is the net torque acting on the merry-go-round about its axle? b. What is the rotational acceleration of the merry-go- round? c. At this rate, what will the rotational velocity of the merry-go-round be after 15 s if it starts from rest? What in d

SP1. A merry-go-round in the park has a radius of 1.8 m and a rotational inertia of 900 kg-m². A child pushes the merry- go-round with a constant force of 80 N applied at the edge and parallel to the edge. A frictional torque of 12 N-m acts at the axle of the merry-go-round. a. What is the net torque acting on the merry-go-round about its axle? b. What is the rotational acceleration of the merry-go- round? c. At this rate, what will the rotational velocity of the merry-go-round be after 15 s if it starts from rest? What in d

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

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Concept explainers

Angular speed, acceleration and displacement

Angular acceleration is defined as the rate of change in angular velocity with respect to time. It has both magnitude and direction. So, it is a vector quantity.

Angular Position

Before diving into angular position, one should understand the basics of position and its importance along with usage in day-to-day life. When one talks of position, it’s always relative with respect to some other object. For example, position of earth with respect to sun, position of school with respect to house, etc. Angular position is the rotational analogue of linear position.

Question

SP1. A merry-go-round in the park has a radius of 1.8 m and a
rotational inertia of 900 kg-m². A child pushes the merry-
go-round with a constant force of 80 N applied at the edge
and parallel to the edge. A frictional torque of 12 N-m acts
at the axle of the merry-go-round.
a. What is the net torque acting on the merry-go-round
about its axle?
b. What is the rotational acceleration of the merry-go-
round?
c. At this rate, what will the rotational velocity of the
merry-go-round be after 15 s if it starts from rest?
d. What is the rotational acceleration of the merry-go-
round if the child stops pushing after 15 s? How long
will it take for the merry-go-round to stop turning?

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