Answer:
a.
Explanation:
In a perfect system then energy can be changed from Kinetic to Gravitational Potential and vice versa without any losses. A common form of loss would be thermal energy, so b. is not the answer. c. is invalid as we want these 2 forms of energy to be transferred between, and d. is invalid as these statements c and a contradict each other.
The closure temperature represents the point when isotopes are no longer free to move out of a crystal lattice.
Answer: Option C
<u>Explanation:</u>
The closure temperature can also be termed as blocking temperature. It is mostly used in radiometric dating. As the temperature decreases, below a certain point the isotopes may get freeze in their lattice positions. And there may be slowing of diffusion.
At the closure temperature, that rate of diffusion will be zero as the isotopes will be no longer free to move out of crystal lattice. So, this is termed as closure or blocking temperature. As the isotopes loose their ability to move, their concentration will remain fixed in their position leading to measurement of radiation dating.
"2 km/hr/s" means that in each second, its engines can increase its speed by 2 km/hr.
If it keeps doing that for 30 seconds, its speed has increased by 60 km/hr.
On top of the initial speed of 20 km/hr, that's 80 km/hr at the end of the 30 seconds.
This whole discussion is of <em>speed</em>, not velocity. Surely, in high school physics,
you've learned the difference by now. There's no information in the question that
says anything about the train's <em>direction</em>, and it was wrong to mention velocity in
the question. This whole thing could have been taking place on a curved section
of track. If that were the case, it would have taken a team of ace engineers, cranking
their Curtas, to describe what was happening to the velocity. Better to just stick with
speed.
Answer:
a = 1.055 x 10¹⁷ m/s²
Explanation:
First, we will find the force on electron:

where,
F = Force = ?
E = Electric Field = 6 x 10⁵ N/C
q = charge on electron = 1.6 x 10⁻¹⁹ C
Therefore,

F = 9.6 x 10⁻¹⁴ N
Now, we will calculate the acceleration using Newton's Second Law:

where,
a = acceleration = ?
m = mass of electron = 9.1 x 10⁻³¹ kg
therefore,

<u>a = 1.055 x 10¹⁷ m/s²</u>