Answer:
No, the acceleration is not always zero.
Explanation:
It does not mean that the acceleration of the particle is zero.
The velocity of wave is different from the velocity of particle.
The acceleration of wave is different from the acceleration of particle.
the acceleration of the particle is given by
where, w is the angular frequency and y is the displacement from the mean position.
So, the acceleration is zero at mean position only and it varies as the position changes.
Answer:
B
Explanation:
for the motion every night, it is because the Earth spins on its axis.
for the changes over a year, this is because the Earth rotates around the sun.
for the changes over hundreds, thousands or millions of years, this is because the whole solar system (including the Earth, of course) rotates with all the other stars in our galaxy around the center of the galaxy. and each star system has its own orbit (similar to the planets in our solar system).
it is very rare to see objects outside of our galaxy without a telescope, but they change too over a long period of time, because our galaxy not only rotates by also moves through the universe, and these other objects move on their own too.
Answer:
If a negatively charged balloon is brought near one end of the rod but not in direct contact, then <u>the negative charges on the balloon repel the same amount of negative charges on the end of the rod that is close to the balloon</u>, and the positive charges stay at the balloon-side of the rod. The total charge of the rod is still zero, but the distribution of the charges are now non-uniform.
W = m.g = weight
g = Gme/Re**2 where G= universal gravitational constant , Re= radius of the earth
me= mass of the earth
therefore it weighs 16 times less
