The question is about unclear since no picture provided. But from the question, it could be guessed that the box is moving back and forth on the frictionless plane at the amplitude of A in simple harmonic motion.
Answer:
D. At x=0, it's acceleration is at a maximum
Explanation:
As the box move forward, it reaches point A and than move backward. Theoretically, the box will move backwards, through its origin, to point -A and then going forward.
Point A is the maximum displacement of the box in this case. At this point, the box instantaneously stop to go backward. Therefore the velocity at that moment is zero.
From point -A, the box travel forward and keep building up speed due to the release in potential energy of the spring. And at point x=0, the velocity become maximum. After point x=0, the velocity of the box slows down due to the conversion of kinetic energy to potential energy of the spring. And as it reaches point A, it reaches zero velocity.
The same can be said as the box travels backward from point A to -A
Answer:increased
Explanation:
It is given that elevator speed is increasing while moving upward i.e.its acceleration is increasing .
This causes the apparent to be increased if measured using weighing machine.
considering upward direction to be positive
N-mg=ma
N=m(g+a)
where N=Normal reaction=Apparent weight
a=acceleration of Elevator
thus you feel as if your weight is increased.
Answer:
mass of the neutron star =3.45185×10^26 Kg
Explanation:
When the neutron star rotates rapidly, a material on its surface to remain in place, the magnitude of the gravitational acceleration on the central material must be equal to magnitude of the centripetal acc. of the rotating star.
That is

M_ns = mass odf the netron star.
G= gravitational constant = 6.67×10^{-11}
R= radius of the star = 18×10^3 m
ω = 10 rev/sec = 20π rads/sec
therefore,

= 3.45185... E26 Kg
= 3.45185×10^26 Kg
Answer:
Condensation
Explanation:
The phase change in which a substance changes from a gas to liquid is Condensation.
There are 3 natural states of matter;
Solids, Liquids, and Gases.
Matter under certain conditions can change from one state to another. When Solids are heated they change into Liquids through the process of Heating. Upon cooling, the Liquids convert to Solid through freezing. When a Liquid such as water is heated, it converts into the Gaseous state through evaporation. Upon cooling, the Gas converts back into the Liquid state through Condensation.