Answer: 12 m/s
Explanation:
If we ignore air resistance, gravity alone will reduce the upward velocity to zero at the top of the flight. As gravity is a conservative force, it will return exactly the same amount of energy to the tennis ball when it returns to the original elevation.
Answer:
The size of an object is directly proportional to the gravity
Explanation:
The size of an object has significant impact on the gravity exerted by such a body.
The more massive a body is, the larger the gravity it exerts.
The reason for this is because of the newton's law of universal gravitation.
- It states that "the gravitational force between two bodies is directly proportional to the product of their masses and inversely proportional to the square of the distances between them".
- As such, gravity is directly proportional to mass
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.
False. A sound wave is an example of a mechanical wave, not an EM wave.
Hope this helps! :)
Answer:
The relationship between the initial stored energy 
and the stored energy after the dielectric is inserted 
is:
c) 
Explanation:
A parallel plate capacitor with 
that is connected to a voltage source 
holds a charge of 
. Then we disconnect the voltage source and keep the charge 
constant . If we insert a dielectric of 
between the plates while we keep the charge constant, we found that the potential decreases as:
The capacitance is modified as:
The stored energy without the dielectric is
The stored energy after the dielectric is inserted is:
If we replace in the above equation the values of V and C we get that
Finally
