The correct choice is D .
Answer:
5 metre.
Explanation:
Wavelength = Velocity / Frequency
= 23,000/ 4,500
= 5 metre.
Answer:
the resistance force is mg cos(-)
Explanation:
Radioactive isotopes of an atom aren't as stable as you would think, so the correct answer is: C. Less Stable
(I can verify this because I took the test.)
Hope this helps! Have a wonderfully wonderful day!
Cheers mate!
Answer:
425 m
Explanation:
From the question,
v = 2x/t.................... Equation 1
Where v = speed of sound in air, x = Length of the lake, t = time.
make x the subject of the equation
x = vt/2............... Equation 2
Given: t = 2.5 s
Constant: v = 340 m/s.
Substitute these values into equation 2
x = 340(2.5)/2
x = 425 m.
Hence the length of the lake is 425 m
