Explanation:
It is given that,
Frequency of vibration, f = 215 Hz
Amplitude, A = 0.832 mm
(a) Let T is the period of this motion. It is given by the following relation as :
![T=\dfrac{1}{f}](https://tex.z-dn.net/?f=T%3D%5Cdfrac%7B1%7D%7Bf%7D)
![T=\dfrac{1}{215}](https://tex.z-dn.net/?f=T%3D%5Cdfrac%7B1%7D%7B215%7D)
![T=4.65\times 10^{-3}\ s](https://tex.z-dn.net/?f=T%3D4.65%5Ctimes%2010%5E%7B-3%7D%5C%20s)
(b) Speed of sound in air, v = 343 m/s
It can be given by :
![v=f\times \lambda](https://tex.z-dn.net/?f=v%3Df%5Ctimes%20%5Clambda)
![\lambda=\dfrac{v}{f}](https://tex.z-dn.net/?f=%5Clambda%3D%5Cdfrac%7Bv%7D%7Bf%7D)
![\lambda=\dfrac{343\ m/s}{215\ Hz}](https://tex.z-dn.net/?f=%5Clambda%3D%5Cdfrac%7B343%5C%20m%2Fs%7D%7B215%5C%20Hz%7D)
![\lambda=1.59\ m](https://tex.z-dn.net/?f=%5Clambda%3D1.59%5C%20m)
Hence, this is the required solution.
Refer to the diagram shown below.
In order for the balloon to strike the professor's head, th balloon should drop by 18 - 1.7 = 16.3 m in the time at the professor takes to walk 1 m.
The time for the professor to walk 1 m is
t = (1 m)/(0.45 m/s) = 2.2222 s
The initial vertical velocity of the balloon is zero.
The vertical drop of the balloon in 2.2222 s is
h = (1/2)*(9.8 m/s²)*(2.2222 s)² = 24.197 m
Because 24.97 > 16.3, the balloon lands in front of the professor, and does not hit the professor.
The time for the balloon to hit the ground is
(1/2)*(9.8)*t² = 18
t = 1.9166 s
The time difference is 2.2222 - 1.9166 = 0.3056 s
Within this time interval, the professor travels 0.45*0.3056 = 0.175 m
Therefore the balloon falls 0.175 m in front of the professor.
Answer:
The balloon misses the professor, and falls 0.175 m in front of the professor.
So, If the silica cyliner of the radiant wall heater is rated at 1.5 kw its temperature when operating is 1025.3 K
To estimate the operating temperature of the radiant wall heater, we need to use the equation for power radiated by the radiant wall heater.
<h3>Power radiated by the radiant wall heater</h3>
The power radiated by the radiant wall heater is given by P = εσAT⁴ where
- ε = emissivity = 1 (since we are not given),
- σ = Stefan-Boltzmann constant = 6 × 10⁻⁸ W/m²-K⁴,
- A = surface area of cylindrical wall heater = 2πrh where
- r = radius of wall heater = 6 mm = 6 × 10⁻³ m and
- h = length of heater = 0.6 m, and
- T = temperature of heater
Since P = εσAT⁴
P = εσ(2πrh)T⁴
Making T subject of the formula, we have
<h3>Temperature of heater</h3>
T = ⁴√[P/εσ(2πrh)]
Since P = 1.5 kW = 1.5 × 10³ W
Substituting the values of the variables into the equation, we have
T = ⁴√[P/εσ(2πrh)]
T = ⁴√[1.5 × 10³ W/(1 × 6 × 10⁻⁸ W/m²-K⁴ × 2π × 6 × 10⁻³ m × 0.6 m)]
T = ⁴√[1.5 × 10³ W/(43.2π × 10⁻¹¹ W/K⁴)]
T = ⁴√[1.5 × 10³ W/135.72 × 10⁻¹¹ W/K⁴)]
T = ⁴√[0.01105 × 10¹⁴ K⁴)]
T = ⁴√[1.105 × 10¹² K⁴)]
T = 1.0253 × 10³ K
T = 1025.3 K
So, If the silica cylinder of the radiant wall heater is rated at 1.5 kw its temperature when operating is 1025.3 K
Learn more about temperature of radiant wall heater here:
brainly.com/question/14548124
Answer:
v = 3.00 x 10⁸ m/s
Explanation:
given,
speed of light in vacuum = 299,792,458 m/s
speed of light in scientific notation to three significant figures
v = 2.99792458 x 10⁸ m/s
by rounding off the speed to three significant figure.
v = 3.00 x 10⁸ m/s
On the fourth place the value is greater than 5 so, on the third place 1 will be added.
now, the speed with three significant figure comes out to be
v = 3.00 x 10⁸ m/s
Answer:
9727160J
Explanation:
Given parameters:
Height of elevator rise = 436m
Force exerted = 22310N
Unknown:
Work done by the elevator lifting mechanism = ?
Solution:
The work done by a body is the force applied to move a body in a specific direction;
Work done = force x distance moved
In this case, the force and distance moved is provided already;
Work done = 22310 x 436 = 9727160J