1. A progressive wave in a stretched string has a speed of 20 ms and a frequency of 100 Hz. What is
the phase difference between two points 25 mm apart?
A zero
B pi/4 rad
c pi/2 rad
D pi tad

Option B

Explanation:

As we know phase difference is equal to

----Eq (1)

where

is the physical difference between two points = 0.025 m

is equal to

Substituting the given values in above equation, we get -

=

Hence, option B is correct

an ion is a charged atom or molecule. it is charged because the number of electrons do not equal the number of protons in the atom or molecule. an atom can acquire a positive charge or a negative charge depending on whether the number of electrons in an atom is greater or less then the number of protons in the atom.

c) up

hope this