Answer:
0.285
Explanation:
Given two forces of different magnitude, it is important to note that the product of normal force and coefficient of kinetic friction should be equal to the sum of these two forces at equilibrium. Therefore, this can be Mathematically expressed as:
where N is normal force,
is coefficient of static friction, F is force and subscripts 1 and 2 represent larger and smaller magnitude forces respectively. Making the subject of the formula then
Since normal force N is also given by mg where m is mass of object and g is acceleration due to gravity then substituting N with mg we obtain that
and substituting the figures given in the question, taking g as 9.81 we obtain that
Hence,the coefficient of kinetic energy is 0.285 as calculated
Answer: A
The diffusion time through the edge is double the diffusion time through the center.
Explanation:
Only the diffusion coefficient, thickness, surface area, distance affects the time it takes a gas such as oxygen to diffuse a given in a medium. The Diffusion time increases with the square of diffusion distance Also, the Increased surface area increases the rate of diffusion or the diffusion time, whereas a thicker membrane reduces the rate of diffusion or time it takes the gas to be permeable. Also, The greater the distance that a substance must travel, the slower the rate of diffusion The diffusion coefficient determines the time it takes a gas to diffuse. Also the Diffusion time is inversely proportional to the diffusion coefficient.
Now, If the edge of a contact lens is double the thickness of the central portion of the lens, then it will take more time for the gas to diffuse through the thicker portion. since its edge is double the central position, then the diffusion time will also be doubled. So Option A is the best answer-
The diffusion time through the edge is double the diffusion time through the center.
How do we look back at our own questions on brainly
Answer:
the magnitude of the vector is 44,40 units
Explanation:
Using the Pythagoras theorem
