Answer:
The fundamental frequency and length of the pipe are 100 Hz and 1.7 m.
Explanation:
Given that,
Frequency f = 550 Hz
Frequency f' = 650 Hz
We know that,
AMT pipe is open pipe.
(b). We need to calculate the length of the pipe
Using formula of organ pipe

For 550 Hz,
...(I)
For 650 Hz,
...(II)
From equation (I) and (II)



(a). We need to calculate the fundamental frequency for n = 1
Using formula of fundamental frequency

put the value of L


Hence, The fundamental frequency and length of the pipe are 100 Hz and 1.7 m.
With a ruler and a calculator
Answer : The velocity of an electron is, 
Explanation :
According to de-Broglie, the expression for wavelength is,

and,

where,
p = momentum, m = mass, v = velocity
So, the formula will be:
.............(1)
where,
h = Planck's constant = 
= wavelength = 
m = mass of electron = 
v = velocity of electron = ?
Now put all the given values in formula 1, we get:


Thus, the velocity of an electron is, 
Answer: colder and drier
Explanation:
Trees don’t grow well in wet climates, nor when they are cold. The wider the rings, the healthier the tree is. Since it was narrow and then wide, was bad climate and then good.