Answer:
L = 0.7 m
Explanation:
This is a resonance exercise, in this case the air-filled pipe is open at both ends, therefore we have bellies at these points.
λ / 2 = L 1st harmonic
λ = L 2nd harmonic
λ = 2L / 3 3rd harmonic
λ = 2L / n n -th harmonic
the speed of sound is related to wavelength and frequencies
v =λ f
f = v /λ
we substitute
f = v n / 2L
the speed of sound in air is v = 343 m / s
suppose that the frequency of f = 980Hz occurs in harmonic n
f₁ = v n / 2L
f₂ = v (n + 1) / 2L
f₃ = v (n + 2) / 2L
we substitute the values
2 980/343 = n / L
2 1260/343 = (n + 1) / L
2 1540/343 = (n + 2) / L
we have three equations, let's use the first two
5.714 = n / L
7.347 = (n + 1) / L
we solve for L and match the expressions
n / 5,714 = (n + 1) / 7,347
7,347 n = 5,714 (n + 1)
n (7,347 -5,714) = 5,714
n = 5,714 / 1,633
n = 3.5
as the number n must be integers n = 4 we substitute in the first equation
L = n / 5,714
L = 0.7 m
The distance traveled by plane flying at 1200 Km/h for 2.5 hours is 3000 Km.
Velocity is a vector quantity. It has both a direction and a magnitude. Speed is used to calculate the magnitude of velocity. The meter per second is the S.I. unit for this. The units km/h and km/s are additional units. [LT-1] is the dimensional equation for it.
The distance traveled by the object is calculated as the product of the velocity with which it was moving and the time interval for which the distance covered is calculated.
Distance traveled = Velocity × Time
Given in the question
Velocity of the plane = 1200 Km/h
Time Traveled = 2.5 h
Put in the value, we get
Distance traveled = 1200 × 2.5
Distance traveled = 3000 Km
Hence, the distance traveled by plane flying at 1200 Km/h for 2.5 hours is 3000 Km.
LEARN MORE ABOUT VELOCITY HERE:
brainly.com/question/6504879
#SPJ9
Answers B and D are true.