A compressor of 45 kg operates at variable speeds from 900 to 1750 rpm. Mounted on...
Fantastic news! We've Found the answer you've been seeking!
Question:
Transcribed Image Text:
A compressor of 45 kg operates at variable speeds from 900 to 1750 rpm. Mounted on the roof of a room, the compressor generates a harmonic force of constant amplitude, transmitted to the roof and causes its vibration. If no isolation is used between the motor and the roof, the noise radiated by the vibrating roof towards the room exceeds the required level by 12dB. A vibration isolator is therefore envisaged to be used to attenuate the force transmission, which will subsequently lead to a noise reduction inside the room. (a) What is the transmissibility required to reduce the noise by 12 dB? (b) By neglecting damping, determine the stiffness of the isolator to achieve the isolation needed. (c) In practice, damping always exists. In that case, is the effective noise reduction higher or lower than 12 dB? Explain why? If a softer isolator is used, in which way the isolation performance would be affected? (d) A compressor of 45 kg operates at variable speeds from 900 to 1750 rpm. Mounted on the roof of a room, the compressor generates a harmonic force of constant amplitude, transmitted to the roof and causes its vibration. If no isolation is used between the motor and the roof, the noise radiated by the vibrating roof towards the room exceeds the required level by 12dB. A vibration isolator is therefore envisaged to be used to attenuate the force transmission, which will subsequently lead to a noise reduction inside the room. (a) What is the transmissibility required to reduce the noise by 12 dB? (b) By neglecting damping, determine the stiffness of the isolator to achieve the isolation needed. (c) In practice, damping always exists. In that case, is the effective noise reduction higher or lower than 12 dB? Explain why? If a softer isolator is used, in which way the isolation performance would be affected? (d)
Expert Answer:
Answer rating: 100% (QA)
aThe transmissibility is the ratio of the amplitude of the ... View the full answer
Related Book For
Retailing Management
ISBN: 978-1259573088
10th edition
Authors: Michael Levy, Barton Weitz, Dhruv Grewal
Posted Date:
Students also viewed these human resource management questions
-
How could MLBAM use a customer relationship management system to improve revenue growth?
-
One hundred randomly selected U.S. parents with at least one child under the age of 18 are surveyed and asked if they have ever spanked their child. The number of parents who have spanked their child...
-
What is a customer relationship management (CRM) program? Describe one CRM program that you have participated in as a customer.
-
2. The beam in the figure is made of material having modulus of elasticity E = 200 GPa . The moment of inertia of segments AB and CD of the beam is I = 6.77 10-6 m, while the moment of inertia of...
-
Vermillion, Inc., a publicly held corporation, pays the following salaries to its executives: Vermillion normally does not pay bonuses, but after reviewing the results of operations for the year, the...
-
As a support worker you have been assigned the duty of caring for an elderly client who is recovering after a knee replacement surgery. You have been hired to give him a bath and personal care and to...
-
A cylinder of diameter \(1.2 \mathrm{~m}\) and length \(7.5 \mathrm{~m}\) rotates at \(90 \mathrm{r}\).p.m. with its axis perpendicular to an air stream with an approach velocity of \(3.6 \mathrm{~m}...
-
The United Kingdom started regulating the size of grocery stores in the early 1990s, and today the average size of a typical U. K. grocery store is roughly half the size of a typical U. S. store and...
-
A manufacturing company reports the following Information for the month of May. Note: Assume all raw materials were used as direct materials. Activities for May Activities for May Advertising expense...
-
Consider the following context-free grammar of expressions E ::= n | (E, E) where n ranges over integers. (a) Present a right-most derivation of the expression ((21, 18), 17). [2 marks] (b) List the...
-
The entity has a standard sales contract, but sales personnel frequently modify the terms of the contract. Sales personnel frequently grant unauthorized and unrecorded sales discounts to customers...
-
Explain how the FOMC determines whether to raise or lower its federal funds rate target. Why doesnt the FOMC respond symmetrically to inflation and unemployment risks?
-
Topco Associates, Inc., is a cooperative association of small and medium-sized regional supermarket chains. Each of its member chains operates independently. All members are required to operate under...
-
An employee was discharged for violating the companys no-solicitation rule in its factory and offices. The employee had persisted in soliciting union membership on company property during lunch...
-
Determine the reactions at \(A\) and \(C\) in Figure P9.39. \(E I\) is constant for all members. 9' 12' A B 60 kips 4.5' D
-
Who is responsible for U.S. monetary policy and what are the roles of the Fed, Congress, and the President?
-
Solve equation by the quadratic formula. List the solutions, separated by commas. 2k - 3k +13=5 k =?
-
Why is it necessary to study the diffusion of molecules in biological systems?
-
What are the two longest rivers in China? What is their overall flow direction (i.e. the same overall flow direction for both rivers) and what causes this? What are the three tiers with respect to...
-
Why do some online retailers include editorials and customer reviews along with product information on their websites? Explain how this may influence the consumers buying behavior.
-
Macy's and Costco have targeted different customer segments. Which retailer would you expect to have a higher gross margin? Higher operating expenses as a percentage of sales? Higher operating profit...
-
Why would sewing pattern manufacturers such as Simplicity (www.simplicity.com/patterns/) and Butterick (https://butterick.mccall.com/) ask $12.95 (or more) on each pattern and then two times a year...
-
For a 2000-line encoder sampled at 5 kHz, what is the speed resolution absent filtering?
-
Correcting for reversal error correction and deadband compensation are special cases of what general technique?
-
Name three benefits of using software R/D conversion compared with hardware R/D converters.
Study smarter with the SolutionInn App