Its to capture light or to focus. don't forget to like. :D
Answer:
887.1Hz
Explanation:
Given parameters:
Speed of sound wave = 330m/s
Wavelength = 0.372m
Unknown:
Frequency = ?
Solution:
To solve this problem, we use the expression below:
Speed = Frequency x wavelength
330 = Frequency x 0.372
Frequency = 887.1Hz
Answer:
A.
Explanation:
Earth is composed of different layers and one layer moves over another due to differences in the densities.
According to the physics of density, a substance having less density floats over a higher density substance. The oceanic crust has more density than the continental crust that is why continental crust float over oceanic crust.
So in the given example, plate B is moving below the plate A, it means plate B is more dense than plate A because plate B is composed of oceanic crust
. <u>For example : continents float over the asthenosphere (a layer below the lithosphere).</u>
Hence, the correct answer is "A
".
Answer
t = 367.77 s = 6.13 min
Explanation:
According to the law of conservation of energy:
![Heat\ Supplied\ By \ Heater = Heat\ Absorbed\ by\ Glass + Heat\ Absorbed\ by\ Water\\Pt = m_gC_g\Delta T_g + m_wC_w\Delta T_w\\](https://tex.z-dn.net/?f=Heat%5C%20Supplied%5C%20By%20%5C%20Heater%20%3D%20Heat%5C%20Absorbed%5C%20by%5C%20Glass%20%2B%20Heat%5C%20Absorbed%5C%20by%5C%20Water%5C%5CPt%20%3D%20m_gC_g%5CDelta%20T_g%20%2B%20m_wC_w%5CDelta%20T_w%5C%5C)
where,
P = Electric Power of Heater = 300 W
t = time required = ?
m_g = mass of glass = 300 g = 0.3 kg
m_w = mass of water = 250 g = 0.25 kg
C_g = speicific heat of glass = 840 J/kg.°C
C_w = specific heatof water = 4184 J/kg.°C
ΔT_g = ΔT_w = Change in Temperature of Glass and water = 100°C - 15°C
ΔT_g = ΔT_w = 85°C
Therefore,
![(300\ W)(t) = (0.3\ kg)(840\ J/kg.^oC)(85^oC)+(0.25\ kg)(4184\ J/kg.^oC)(85^oC)\\](https://tex.z-dn.net/?f=%28300%5C%20W%29%28t%29%20%3D%20%280.3%5C%20kg%29%28840%5C%20J%2Fkg.%5EoC%29%2885%5EoC%29%2B%280.25%5C%20kg%29%284184%5C%20J%2Fkg.%5EoC%29%2885%5EoC%29%5C%5C)
<u>t = 367.77 s = 6.13 min</u>