Answer:
A: Sound waves produce an echo
Explanation:
because the cup is a hard smooth surface you can hear the voice
Oxygen is diatomic, so its degree of freedom, (f1)= 5,
also its number of moles, n1= 1
Helium is monoatomic, so its degree of freedom (f2)= 3
and its number of moles given is, n2=2
Now using formula of effective degree of freedom of mixture, (f), we have:
f= (f1n1+f2n2)/(n1+n2)
= (5*1 + 3*2)/ (1+3)
=11/3
Also, from first law of thermodynamics;
U= n Cv. T = nRT(f2)
or, Cv = R. (f/2) (n & T cancel)
We know f=11/6,
substituting the value in above relation, we have:
Cv= R. 11/3*2
= R. 11/6
Also, Cp-Cv = R
or, Cp- R.(11/6)= R
or, Cp= R(11/6 )+1
= 17/6 R
Therefore, Cp/Cv = 17/11
Air, water , atomic acid , and pocket rocket
Answer:A
Explanation:
In R-L circuit current is given by
![i=i_0\left [ 1-e^{\frac{-t}{L/R}}\right ]](https://tex.z-dn.net/?f=i%3Di_0%5Cleft%20%5B%201-e%5E%7B%5Cfrac%7B-t%7D%7BL%2FR%7D%7D%5Cright%20%5D)
where i=current at any time t
R=resistance
L=Inductance
at t=0 
approaches to 1
therefore ![i=i_0\left [ 1-1\right ]](https://tex.z-dn.net/?f=i%3Di_0%5Cleft%20%5B%201-1%5Cright%20%5D)
i=0
when t approaches to 
, approaches to zero
thus 
thus we can say that initially circuit act as broken wire with zero current
and it increases exponentially with time and act as ordinary connecting wire
Answer:
B
Explanation:
B. Women have straighter teeth.
