Can you please translate to English?
a,b,c is your answer light and sound are not considered matter and heat is energy created from matter and electricity is particles moving basically therefore electricity is matter hope this helps
<span>Velocity is a vector and it has both speed and direction. It takes a force to change direction just as it does to change speed</span>. In order to have a constant velocity the object must maintain a constant direction and speed. Hope this answers the questions. Have a nice day.
Answer and Explanation:
Data provided in the question
Force = 50N
Length = 5mm
diameter = 2.0m = 
Extended by = 0.25mm = 
Based on the above information, the calculation is as follows
a. The Stress of the wire is

here area of circle = perpendicular to the are i.e cross-sectional i.e
= 
= 
Now place these above values to the above formula

= 15.92 MPa
As 1Pa = 1 by N m^2
So,
MPa = 10^6 N m^2
b. Now the strain of the wire is

= 