Answer:
Tt = 70 + 135e^-0.031t
13 minutes
Explanation:
Given that :
Initial temperature, Ti = 205°
Temperature after 2.5 minutes = 195°
Temperature of room, Ts= 70
Using the relation :
Tt = Ts + Ce^-kt
Temperature after time, t
When freshly poured, t = 0
205 = 70 + Ce^-0k
205 = 70 + C
C = 205 - 70 = 135°
T after 2.5 minutes to find proportionality constant, k
Tt = Ts + Ce^-kt
195 = 70 + 135e^-2.5k
125 = 135e^-2.5k
125 / 135 = e^-2.5k
0.9259 = e^-2.5k
Take In of both sides :
−0.076989 = - 2.5k
k = −0.076989 / - 2.5
k = 0.031
Equation becomes :
Tt = 70 + 135e^-0.031t
t when Tt = 160
160 = 70 + 135e^-0.031k
90 = 135e^-0.031t
90/135 = e^-0.031t
0.6667 = e^-0.031t
In(0.6667) = - 0.031t
−0.405465 = - 0.031t
t = 0.405465/ 0.031
t = 13.071
t = 13 minutes
Answer: 
Explanation:
Combined gas law is the combination of Boyle's law, Charles's law and Gay-Lussac's law.
The combined gas equation is,
where,
= initial pressure of gas at STP = 1 atm
= final pressure of gas = 2.67 atm
= initial volume of gas = 
= final volume of gas = ?
= initial temperature of gas at STP = 
= final temperature of gas = 
Now put all the given values in the above equation, we get:
Thus the final volume will be
B. Frequency remains unchanged because the energy in a photon is E=hf. So if the frequency changes so does the energy and that doesn't happen to EM waves entering a medium by the conservation of energy
Mechanical weathering is the physical breakdown of rock by environmental factors. This process is always at work, and there are a number of different types of mechanical weathering. Thermal expansion is the tendency for minerals to expand and contract based on temperature.
Answer:
OptionC)
Explanation:
As muscle size increase gradually when we become adolsence and it increases in boys..
