Sound waves are mechanical(?) waves?
Explanation:
The charge on the electron is, 
The electric field at a distance r from the electron is :

Where
k is the electrostatic constant, 
We know that the electric field lines starts from positive charge and ends at the negative charge. Also, for a positive charge the field lines are outwards while for a negative charge the field lines are inwards.
So, the correct option is " the electric field is directed toward the electron and has a magnitude of
. Hence, this is the required solution.
Answer:
the energy required for the extension is 12.25 J
Explanation:
Given;
force constant of trampoline spring, k = 800 N/m
extension of trampoline spring, x = 17.5 cm = 0.175 m
The energy required for the extension is calculated as;
E = ¹/₂kx²
E = 0.5 x 800 x 0.175²
E = 12.25 J
Therefore, the energy required for the extension is 12.25 J
Answer:
8.333*10^-6 ohms
Explanation:
Resistivity of a material is expressed as;
p = RA/l
R is the resistance of the material
A is the cross sectional area
l is the length of the material
Given
R = 5 ohms
A = 0.5mm^2
A = 5 * 10^-7m^2
l = 30cm = 0.3m
Substitute into the formula;
p = (5 * 5 * 10^-7m^2)/0.3
p = 25 * 10^-7/0.3
p = 0.0000025/0.3
p = 8.333*10^-6
Hence its resistivity at 20 degrees Celsius is 8.333*10^-6 ohms
D, it depends. For water, the solubility increases as it get hotter, up to 100 degrees, but in some cases, liquids behave the opposite way.