Explanation :
It is given that an oscillator makes 360 oscillations in 3 minutes.
(a) Using unitary method :
No. of vibrations in one minute is, 
So, no of vibrations in one minute is 120.
(b) Similarly,
3 minutes = 180 seconds
No of vibrations in one second is 
So, the no of vibrations in one second is 2.
(c) Time period of the wave is given by :


The time period of the wave is 0.5 s
(d) The no of vibation per second is called as its frequency.


Hence, this is the required solution.
Velocity, unlike speed, includes a direction.
Velocity is a vector quantity which is defined by magnitude and direction.
Speed is a scalar quantity. It is the rate at which an object moves regardless of which direction.
Answer:
Artificial is the BEST synonym for synthetic
Answer:
4.39 x 10^-19 J
Explanation:
q1 = 1.6 x 10^-19 C
q2 = - 1.6 x 10^-19 C
r1 = 3 x 10^-10 m
r2 = 7 x 10^-10 m
The formula for the potential energy is given by
U1 = k q1 q2 / r1 = - (9 x 10^9 x 1.6 x 10^-19 x 1.6 x 10^-19) / (3 x 10^-10)
U1 = - 7.68 x 10^-19 J
U2 = k q1 q2 / r2 = - (9 x 10^9 x 1.6 x 10^-19 x 1.6 x 10^-19) / (7 x 10^-10)
U2 = - 3.29 x 10^-19 J
Change in potential energy is
U2 - U1 = - 3.29 x 10^-19 + 7.68 x 10^-19 = 4.39 x 10^-19 J