' B ' is the only true one.
Answer:
False
Explanation:
the total distance of a moving body is always positive
Distance is the total distance between any two points
A block of plastic released under water will come up to the surface of the water because the density of the plastic is less than the density of water.
<h3>
What is density?</h3>
Density is the amount of mass a substance contains per its unit volume. It means the number of particles that can be packed into a unit space of that substance.
<h3>
How does density determine whether an object will float or sink?</h3>
When an object is immersed in a liquid, it experiences two forces - gravitational force and an upward buoyant force called upthrust. If the density of the object is more than the density of the liquid, gravitational force will be greater than upthrust and the object will sink, but if the density of the object is less than the density of the liquid, upthrust will be greater than gravitational force and the object will float. That is why a block of plastic will come up to the surface when released under water, because it is less dense than water.
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Answer:
E = 1.711 MeV
Explanation:
From the law of the conservation of energy:

where,
the kinetic energy of positron and electron = 1.2 MeV
Rest energy of the electron and the positron = 0.511 MeV
E = Energy of Photon = ?
Therefore,

<u>E = 1.711 MeV</u>
The angle above the horizontal of the motion of mass A + B after the collision. as well as others are mathematically given as

- vf/vA= 0.94
- 2vf^2 / 5vA^2 = 0.35
<h3>What is
Collison equilibrium?</h3>
According to the collision hypothesis of chemistry, chemical reactions happen when two molecules or atoms collide.
Generally, the equation for Collison equilibrium is mathematically given as
For horizontal motion
mvAx+m2vAx = 2mvfx
For vertical motion
-mvAy+m2vAy = 2mvfy
vfy = 1/2 vAy


(b)

vf/vA= 0.94
(c)
![Ef/Ei = \frac{(1/2 * (2m) * (vf)^2) }{ (1/2 * m * (vA)^2) + 1/2*m*(2vA)^2) ]}](https://tex.z-dn.net/?f=Ef%2FEi%20%3D%20%5Cfrac%7B%281%2F2%20%2A%20%282m%29%20%2A%20%28vf%29%5E2%29%20%7D%7B%20%281%2F2%20%2A%20m%20%2A%20%28vA%29%5E2%29%20%2B%201%2F2%2Am%2A%282vA%29%5E2%29%20%5D%7D)
2vf^2 / 5vA^2 = 0.35
In conclusion, The angle above the horizontal of the motion of mass A + B after the collision. as well as others

vf/vA= 0.94
2vf^2 / 5vA^2 = 0.35
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