Hi there,
Matter is sometimes invisible. Most invisible matters are gas because it consists of tiny air molecules.
Hope this helps!
Sincerely,
Dus4nR
Well are having freckles recessive or dominant?
To calculate the length of the wire, we use formulas,
(A)
(B)
Here, R is the resistance of the wire, I is the current flows through wire and V is potential difference. A is cross sectional area of wire and
is the density of copper wire and is value,
.
Given 
Substituting the values of I and V in equation (A ) we get,

Now from equation (B),

Therefore,

Thus the length of the copper wire is 177.9 m.
Answer:
(B) 1.41 x 10^{10} N/m^{2}
Explanation:
diameter of wire (d) = 0.6 mm = 0.0006 m
radius of wire (r) = 0.0006/2 = 0.0003 m
tension (force F) = 20 N
percentage strain = 0.5 %
what is the Young's modulus?
Young's modulus =
where
stress = 
stress = 
stress =70735530.3 N/m^{2}
- strain = percentage strain ÷ 100
strain = 0.5 ÷ 100 = 0.005
therefore Young's modulus =
=
= 1.41 x 10^{10} N/m^{2}