Answer:
Sundial is an instrument showing the time by the shadow of a pointer cast by the sun on to a plate marked with the hours of the day.
Answer:
164.87 J
Explanation:
From the question,
Work done (W) = mghcosθ........................ Equation 1
Where m = mass of the box, h = height, g = acceleration due to gravity, θ = angle to the vertical
Given: m = 25 kg, h = 2.6 meters, θ = 75°.
Constant: g = 9.8 m/s²
Substitute these value into equation 1
W = 25×9.8×2.6×cos75°
W = 164.87 J.
Answer:
f3 = 102 Hz
Explanation:
To find the frequency of the sound produced by the pipe you use the following formula:

n: number of the harmonic = 3
vs: speed of sound = 340 m/s
L: length of the pipe = 2.5 m
You replace the values of n, L and vs in order to calculate the frequency:

hence, the frequency of the third overtone is 102 Hz