<h2>Option 1 is correct option .</h2>
Explanation:
The velocity of sound depends upon temperature . The temperature is different at different altitudes .
The velocity of sound has no effect of pressure . Thus at different altitudes , if pressure is different , it makes no difference .
Therefore the speed of sound varies rapidly with altitude , due to variation of temperature .
It also depends on the nature of medium . which also varies with altitude .
Moreover we cannot get distance by dividing time interval with 3 .
Answer:
the angle the ladder makes with the floor as seen by an observer on Earth is 71.9°
Explanation:
Given the data in the question and as illustrated in the diagram below.
speed of the ship v = 0.90c
base of the ladder from the wall x₀ = 3.0 m
top of the later above the floor y = 4.0 m
we determine angle θ.
from the diagram,
tanθ = y/x₀
tanθ = y / x₀√( 1 - v²/c² )
we substitute
tanθ = 4.0 / 3.0√( 1 - ((0.9c)²/c²) )
tanθ = 4.0 / 3.0√( 1 - ((0.9²)c²/c²) )
tanθ = 4.0 / 3.0√( 1 - (0.9²) )
tanθ = 4.0 / 3.0√( 1 - 0.81 )
tanθ = 4.0 / 3.0√0.19
tanθ = 4.0 / 1.30766968
tanθ = 3.058876
θ = tan⁻¹( 3.058876 )
θ = 71.8965 ≈ 71.9°
Therefore, the angle the ladder makes with the floor as seen by an observer on Earth is 71.9°
Answer:
Moment of Force, M = 51.6 lbf-ft
Explanation:
Given,
The fishing rod AB of length, L = 6 ft
The force acting on the rod, F = 8.6 lbf
The moment of force about A is given as the product of force and perpendicular distance. It is given by the formula
M = F x L
Substituting the given values in the above equation
M = 8.6 lbf x 6 ft
= 51.6 lbf-ft
The moment about A of the force exerted by the line at B is, M = 51.6 lbf-ft
Answer:
![T_f=57.21\ ^{\circ}C](https://tex.z-dn.net/?f=T_f%3D57.21%5C%20%5E%7B%5Ccirc%7DC)
Explanation:
Given:
- mass of aluminium,
![m_a=0.2\ kg](https://tex.z-dn.net/?f=m_a%3D0.2%5C%20kg)
- initial temperature of the aluminium cylinder,
![T_{ia}=-20\ ^{\circ}C](https://tex.z-dn.net/?f=T_%7Bia%7D%3D-20%5C%20%5E%7B%5Ccirc%7DC)
- mass of coffee,
![m_c=0.5\ kg](https://tex.z-dn.net/?f=m_c%3D0.5%5C%20kg)
- initial temperature of coffee,
![T_{ic}=85\ ^{\circ}C](https://tex.z-dn.net/?f=T_%7Bic%7D%3D85%5C%20%5E%7B%5Ccirc%7DC)
- specific heat of coffee (assuming water),
![c_w=1000\ J.kg^{-1}.^{\circ}C^{-1}](https://tex.z-dn.net/?f=c_w%3D1000%5C%20J.kg%5E%7B-1%7D.%5E%7B%5Ccirc%7DC%5E%7B-1%7D)
- specific heat of aluminium,
![c_a=900\ J.kg^{-1}.^{\circ}C^{-1}](https://tex.z-dn.net/?f=c_a%3D900%5C%20J.kg%5E%7B-1%7D.%5E%7B%5Ccirc%7DC%5E%7B-1%7D)
When the coffee and the aluminium cylinder come in contact then heat released by the coffee is equal to the heat gained by the aluminium.
<u>Mathematically:</u>
![Q_c=Q_a](https://tex.z-dn.net/?f=Q_c%3DQ_a)
![m_c.c_w. (T_{ic}-T_f)=m_a.c_a.(T_f-T_{ia})](https://tex.z-dn.net/?f=m_c.c_w.%20%28T_%7Bic%7D-T_f%29%3Dm_a.c_a.%28T_f-T_%7Bia%7D%29)
![0.5\times 1000\times (85-T_f)=0.2\times 900\times (T_f-(-20))](https://tex.z-dn.net/?f=0.5%5Ctimes%201000%5Ctimes%20%2885-T_f%29%3D0.2%5Ctimes%20900%5Ctimes%20%28T_f-%28-20%29%29)
![42500-500\times T_f=180\times T_f+3600](https://tex.z-dn.net/?f=42500-500%5Ctimes%20T_f%3D180%5Ctimes%20T_f%2B3600)
is the final temperature of agreement.
Explanation:
Complete the first and second sentences, choosing the correct answer from the given ones.
1. T = 100 K
![^{\circ}C=K-273](https://tex.z-dn.net/?f=%5E%7B%5Ccirc%7DC%3DK-273)
Put T = 100 K
![T=100-273=-173^{\circ} C](https://tex.z-dn.net/?f=T%3D100-273%3D-173%5E%7B%5Ccirc%7D%20C)
A temperature of 100 K corresponds on a Celsius scale to (-173 °C)
2. T = 50 °C
![K=^{\circ}C+273\\\\K=50+273\\\\T=323\ K](https://tex.z-dn.net/?f=K%3D%5E%7B%5Ccirc%7DC%2B273%5C%5C%5C%5CK%3D50%2B273%5C%5C%5C%5CT%3D323%5C%20K)
So, At 50 °C, it corresponds to a Kelvin scale of 323 K.