<h3>
Answer:</h3>
B. (PE)beginning = (KE)end
<h3>
Explanation:</h3>
<u>We are given;</u>
- Mass of an object is 72.0 kg
- Velocity of the body before it hits the ground is 79.0 m/s
We are required to determine the relationship between the potential energy and kinetic energy before the fall.
- When an object is at the highest point, it has maximum potential energy and minimum kinetic energy.
- This is because potential energy is directly proportional to the height of an object above the earth's surface.
- On the other hand, when an object attains the highest speed it has maximum kinetic energy and minimum kinetic energy.
In this case;
- The velocity of the object when hitting the ground is maximum and thus the object will have maxim,um kinetic energy.
- As the object falls towards the ground the potential energy is being converted to kinetic energy.
- Therefore, the potential energy at the beginning will be equal to the kinetic energy at the end when the object is on the ground.
- We can therefore, conclude that, (PE)beginning = (KE)end
Answer:
True
Explanation:
If a thin, spherical, conducting shell carries a negative charge, We expect the excess electrons to mutually repel one another, and, thereby, become uniformly distributed over the surface of the shell. The electric field-lines produced outside such a charge distribution point towards the surface of the conductor, and end on the excess electrons. Moreover, the field-lines are normal to the surface of the conductor. This must be the case, otherwise the electric field would have a component parallel to the conducting surface. Since the excess electrons are free to move through the conductor, any parallel component of the field would cause a redistribution of the charges on the shell. This process will only cease when the parallel component has been reduced to zero over the whole surface of the shell
According to Gauss law
∅ = EA =-Q/∈₀
Where ∅ is the electric flux through the gaussian surface and E is the electric field strength
If the gaussian surface encloses no charge, since all of the charge lies on the shell, so it follows from Gauss' law, and symmetry, that the electric field inside the shell is zero. In fact, the electric field inside any closed hollow conductor is zero
The correct option is D.
Destructive interference is said to occur when two waves superpose in such a way that they cancel each other out. The two waves are usually of equal frequency and opposite phase, the negative displacement of one wave collides with the positive displacement of the other wave, thus cancelling each other out.<span />
A radioactive isotope will release alpha particles and become more stable, and becomes a different element.
Answer:
649kg/m^3
Explanation:
Let p be the density of this particular object.
Formula for density:
![p = \frac{mass \: (in \: kg)}{volume \: (in \: {m}^{3}) }](https://tex.z-dn.net/?f=p%20%3D%20%20%5Cfrac%7Bmass%20%5C%3A%20%28in%20%5C%3A%20kg%29%7D%7Bvolume%20%5C%3A%20%28in%20%5C%3A%20%20%7Bm%7D%5E%7B3%7D%29%20%7D%20)
We can substitute the givenmass and volume to find density of the object.
![p = \frac{25kg}{0.0385 {m}^{3} } \\ = 649kg \: per \: {m}^{3}](https://tex.z-dn.net/?f=p%20%3D%20%20%5Cfrac%7B25kg%7D%7B0.0385%20%7Bm%7D%5E%7B3%7D%20%7D%20%20%5C%5C%20%20%3D%20649kg%20%5C%3A%20per%20%5C%3A%20%20%7Bm%7D%5E%7B3%7D%20)
Therefore the density of this object is 649kg/m^3.