Answer:
kinetic energy + potential energy
There are different forces acting on an object like nuclear force , gravitational force...plus external forces like friction and other..
net sum of all these is resultnat
Diffuse reflection have a great day
Answer:

Explanation:
From the question we are told that:
Frequency of 3rd harmonics 
Frequency of 5th harmonics 
Generally the equation for Wavelength at 3rd Harmonics is mathematically given by

Therefore

Generally the equation for Wavelength at 1st Harmonics is mathematically given by

Therefore

Generally the equation for the frequency of the first harmonic is mathematically given by



The width of the playroom is 4 m