Answer:
2.62seconds
Explanation:
Speed is defined as the ratio of the distance covered by a body with respect to time.
Speed v = Distance (s)/Time (t)
For a traveling sound wave, the distance between the source of a sound and the reflector is '2S'.
Speed v = 2 × distance (S)/Time (T)
V = 2S/t
2S = vt
Given speed of the wave = 342m/s
Distance covered = 450m
t = 2S/v
t = (2×450)/343
t = 900/343
t = 2.62seconds
It will take him 2.62seconds for him to hear his own voice echo off of the wall.
Complete Question
A flywheel in a motor is spinning at 510 rpm when a power failure suddenly occurs. The flywheel has mass 40.0 kg and diameter 75.0 cm . The power is off for 40.0 s , and during this time the flywheel slows down uniformly due to friction in its axle bearings. During the time the power is off, the flywheel makes 210 complete revolutions. At what rate is the flywheel spinning when the power comes back on(in rpm)? How long after the beginning of the power failure would it have taken the flywheel to stop if the power had not come back on, and how many revolutions would the wheel have made during this time?
Answer:
![\theta=274rev](https://tex.z-dn.net/?f=%5Ctheta%3D274rev)
Explanation:
From the question we are told that:
Angular velocity ![\omega=510rpm](https://tex.z-dn.net/?f=%5Comega%3D510rpm)
Mass ![m=40.kg](https://tex.z-dn.net/?f=m%3D40.kg)
Diameter d ![75=>0.75m](https://tex.z-dn.net/?f=75%3D%3E0.75m)
Off Time ![t=40.0s](https://tex.z-dn.net/?f=t%3D40.0s)
Oscillation at Power off ![N=210](https://tex.z-dn.net/?f=N%3D210)
Generally the equation for Angular displacement is mathematically given by
![\theta_{\infty}=\frac{w+w_0}{t}t](https://tex.z-dn.net/?f=%5Ctheta_%7B%5Cinfty%7D%3D%5Cfrac%7Bw%2Bw_0%7D%7Bt%7Dt)
![w=\frac{2*\theta_{\infty}}{t}-w_0](https://tex.z-dn.net/?f=w%3D%5Cfrac%7B2%2A%5Ctheta_%7B%5Cinfty%7D%7D%7Bt%7D-w_0)
![w=\frac{28210}{40*(\frac{1}{60})}-510](https://tex.z-dn.net/?f=w%3D%5Cfrac%7B28210%7D%7B40%2A%28%5Cfrac%7B1%7D%7B60%7D%29%7D-510)
![w=120rpm](https://tex.z-dn.net/?f=w%3D120rpm)
Generally the equation for Time to come to rest is mathematically given by
![t=(\frac{\omega_0}{\omega_0-\omega})t](https://tex.z-dn.net/?f=t%3D%28%5Cfrac%7B%5Comega_0%7D%7B%5Comega_0-%5Comega%7D%29t)
![t=(\frac{510}{510-120rpm})(40.0)(\frac{1}{60})](https://tex.z-dn.net/?f=t%3D%28%5Cfrac%7B510%7D%7B510-120rpm%7D%29%2840.0%29%28%5Cfrac%7B1%7D%7B60%7D%29)
![t=0.87min](https://tex.z-dn.net/?f=t%3D0.87min)
Therefore Angular displacement is
![\theta =(\frac{120+510}{2})0.87](https://tex.z-dn.net/?f=%5Ctheta%20%3D%28%5Cfrac%7B120%2B510%7D%7B2%7D%290.87)
![\theta=274rev](https://tex.z-dn.net/?f=%5Ctheta%3D274rev)
Answer:
Sublimation
Explanation: When a solid goes straight to a gas it's called sublimation.
All of the above, work is a measurement of energy transfer, in Joules.
Potential energy = Joules
Kinetic energy = Joules
The key thing here is that anything having to do with just energy or energy transfer is measured in joules.
I hope this is what you are looking for
P1 = 270 kPa
V1 = 1 L
P2 = 540 kPa
V2 = ?
Use Boyle's Law:
P1V1 = P2V2
V2 = P1 V1 / P2
V2 = 270 x 1 / 540
V2 = 0.5 L