The spring is neither stretched nor compressed. an object having a mass m is attached to the free end of the spring. consider an action
Answer:
<em>About four million tons of </em><em><u>matter</u></em><em> are converted to energy in the Sun’s core every second</em>
Explanation:
<u>The Sun
</u>
It's estimated that The Sun fuses near 600 million tons
of hydrogen into helium every second. As a result, 4 million tons of matter are converted to energy every second according to Einstein's equation 
Answer:
853776 J
Explanation:
The work-energy needs to pump water out of the pool is the product of the weight of water and distance h
E = Wh = mgh
Since water mass is a body of water we can treat it as the product of density 1000kg/m3 and volume, which is the product of base area and uniform height h

Therefore:
![E = mgh = g\rho A\int\limits^{2.2}_0 {h} \, dh\\E = 9.8*1000*30*12[h^2/2]^{2.2}_0 = 1764000(2.2^2 - 0^2) = 853776 J](https://tex.z-dn.net/?f=E%20%3D%20mgh%20%3D%20g%5Crho%20A%5Cint%5Climits%5E%7B2.2%7D_0%20%7Bh%7D%20%5C%2C%20dh%5C%5CE%20%3D%209.8%2A1000%2A30%2A12%5Bh%5E2%2F2%5D%5E%7B2.2%7D_0%20%3D%201764000%282.2%5E2%20-%200%5E2%29%20%3D%20853776%20J)
The complete question is
What modifications did kepler make to copernicus’s model? check all that apply. planetary orbits are elliptical. planets closer to the sun move faster. planets spin in an epicycle while orbiting earth. venus has phases due to its orbiting of the sun. earth’s rotation causes the rising and setting of the sun.
Answer:
Planetary orbits are elliptical.
Planets closer to the Sun move faster.
Explanation:
The first option is based on the first law that states that the planets orbit the sun in ellipses, with the sun at one focus of the ellipse.
The second option is based on the third law that states that the square of the time of revolution about the sun is directly proportional to the cube of the mean radius of orbit of the planet.