Answer:
The mass of the Al-duckie should be 30 kg.
Explanation:
We will use the first law of thermodynamics:
ΔU = m·Cv·ΔT
Since the specific heat of water is 4.185 J(gºC), the change in the water's internal energy would be:
ΔU = 100 kg · 4.185 J(gºC) · (42ºC - 38ºC) = 1674 KJ
Given that no heat is lost, all the internal energy that the water loses while cooling down will transfer to the duckie. So, if the duckie has ΔU = 1674 KJ and its final temperature is the desired 38 ºC, we can calculate its mass using the first law again:
![m=\frac{\Delta{U}}{Cv{\Delta{T}}}=\frac{1674}{0.9*[38-(-24)]}=30Kg](https://tex.z-dn.net/?f=m%3D%5Cfrac%7B%5CDelta%7BU%7D%7D%7BCv%7B%5CDelta%7BT%7D%7D%7D%3D%5Cfrac%7B1674%7D%7B0.9%2A%5B38-%28-24%29%5D%7D%3D30Kg)
When solid material expands in response to an increase in temperature (thermal expansion), it can increase in length in a process known as linear expansion. for an example application of expansion and contraction.
examples =
(1) Changing of shape and dimensions of objects such as doors.
(2) Wall collapsing due to bulging.
(3) Cracking of glass tumbler due to heating.
(4) Bursting of metal pipes carrying hot water or steam are some of the disadvantages of thermal expansion of matter.
Answer:
1.3m/s
Explanation:
Data given,
Mass,m=1.0kg,
Amplitude,A=0.10m,
Frequency,f=2.0Hz.
From the equation of a simple harmonic motion, the displacement of the object at a given time is define as

we can express the velocity by the derivative of the displacement,
Hence

at equilibrium, the velocity becomes

Hence if we substitute values we arrive at

Answer:
The answer is "c,d,e, and g".
Explanation:
The correct choices can be defined as follows:
- Higher-frequency microwaves aren't used in any of these systems.
- Infrared waves aren't seen in each of these technologies.
- Its shortest wavelength of all of the technologies listed is the above radiation generated by certain wireless networks.
- These devices all produce waves of wavelengths ranging from 0.10 to 10.0 cm.
Answer:
(1) chess is played by him
(2) The great black engine was seen by her
(3) Arrangements for functions had been made by him
(4) A meeting is being attended by Raman
= when the last of the guests left, I went back into the hall to look for my mobile phone that I had kept on the table, I found that my mobile phone was not there. I felt freaked and I asked to every member of my family about my phone, but nobody had idea about that. then there was a phone call made by my uncle to my father, that his son had taken the mobile by mistake. After sometime, My uncle came to return my mobile. Then I took a sigh of relief .
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