Answer:
μ = 0.385
Explanation:
Given that,
The mass of the student, m = 69 Kg
The horizontal force applied, F = 260 N
The normal force acting on the body, weight = mg = 69g N
= 676.2 N
The coefficient of friction acting on a body is equal to the force acting on the body to the normal force acting on the body due to gravitation.
The formula for coefficient of friction,
μ = F / N
Substituting the values in the above equation,
μ = 260 N / 676.2 N
= 0.385
Hence, the coefficient of friction, μ = 0.385
In physical chemistry, the mean free path is the average distance between the atoms during collision. Its formula is

where d is the diameter of the Nitrogen atom (d = 310 x 10^-7 m), Na is Avogadro's number (Na=6.022 x 10^23), R is the gas constant (8.314 J/mol-K), T is the absolute temperature (T= 20 + 273 = 293 K). Substituting the values,
P = 6.32 x 10^-13 Pascals
Answer:
Thomson
Explanation:
Thomson in 1904 soon after the discovery of the electron, but before the discovery of the atomic nucleus, the model tried to explain two properties of atoms then known: that electrons are negatively-charged particles and that atoms have no net electric charge.
Answer:
3amperes
Explanation:
current = voltage ÷ resistance = 90÷30= 3amperes
Usually, sound needs a medium to travel through, like a vacuum for example.
Light does not need a medium to travel, and since air is considered a medium, light is not dependent on that.
On the other hand, sound needs a medium to travel through, and outer space doesn't contain space, therefore, no sound.