1)Wheel barrow does not make oscillation movement
2)Number of oscillations in one second is known as frequency.
3) Frequency is the reciprocal of wavelength.
4) The period of spring is 4 second.
Step-by-step explanation:
1) Wheel barrow does not make oscillation movement as they move as push and pull motion. The other instruments like spring, pendulum and turning fork will behave in oscillation movement.
2) Number of oscillations in one second is known as frequency. Since, frequency is the measure of repetition in a given time interval, it is found by calculating the number of oscillations in one second.
3) Frequency is the reciprocal of wavelength. The product of frequency and wavelength is defined as velocity. So frequency will be defined as the reciprocal of wavelength.
4) As it is making 20 oscillations in 5 seconds, then the time taken for single oscillation is considered as period of spring.
![Period of spring = (No. of Oscillations)/(Time)\\\\Period of spring = (20)/(5)= 4 second.](https://img.qammunity.org/2021/formulas/physics/middle-school/t08dl50rc28iirl390lzhuvomynmjdtf3x.png)
So the period of spring is 4 second.