Answer:
v_f = 24.3 m / s
Explanation:
A) In this exercise there is no friction so energy is conserved.
Starting point. On the roof of the building
Em₀ = K + U = ½ m v₀² + m g y₀
Final point. On the floor
Em_f = K = ½ m v_f²
Emo = Em_g
½ m v₀² + m g y₀ = ½ m v_f²
v_f² = v₀² + 2 g y₀
let's calculate
v_f = √(10² + 2 9.8 25)
v_f = 24.3 m / s
They’re both describing factors of something
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.
Answer:
C) The rate of change from potential to kinetic energy is exponential.
Explanation:
As we know that total mechanical energy must be conserved here
As we know that there is no friction force on this system of electromagnet and nail
So here we can say that that
Magnetic potential energy of the nail + electromagnet system will convert into kinetic energy of the nail as it is released.
So we will have
Initial potential energy = work done to move it away by 10 cm


now as the nail is released then this potential energy will start to convert into kinetic energy
So here correct answer must be
C) The rate of change from potential to kinetic energy is exponential.
Answer:
the branch of mechanics concerned with the interaction of electric currents with magnetic fields or with other electric currents.
Explanation: