Answer:
Frequency is 
Explanation:
Distance between source 1 from the receiver , 
Distance between source 2 from the receiver , 
Now ,
Path difference , 
We know, for constructive interference path difference should be integral multiple of wavelength .
Therefore, 
It is given that n = 1,
Therefore, 
Frequency can be found by , 
Hence, this is the required solution.
Answer:
C. An ion with a +2 charge
Explanation:
I guess
Answer:
7,166 hrs =430 minutes
Explanation:
Since both train are on the same track, going one towards the other, the relative speed is the addition of both, then the time they need to meet, and consistently crash, is the time that (65mph + 55 mph)=120mph need to travel the total distance of 860 miles, of course in this case one part is traveled by the first train and the rest by the other. Then to find the time we use a three rule
1 h --->120mi
X ---->860mi, then X=(860 mi* 1h)/120 mi = 43/6 hrs= 7,16666 hrs, turning this into minutes need that we notice 1h=60min, then 43/6 hrs *60 min/hrs = 430 minutes.
