Answer:
Friction is when a force is applied or done by weight dragging onto something.
Explanation:
Gravity is when an object is getting pulled toward the center of what is attracting it. And applied force is when someone/sommething is applying force.
Neglecting friction and air resistance, the first hill must be built 4 times higher than it is now.
Answer:
Part a)

Part b)
if both sides are rough then it will reach the same height on the other side because the energy is being conserved.
Part c)
Since marble will go to same height when it is rough while when it is smooth then it will go to the height

so on smooth it will go to lower height
Explanation:
As we know by energy conservation the total energy at the bottom of the bowl is given as

here we know that on the left side the ball is rolling due to which it is having rotational and transnational both kinetic energy
now on the right side of the bowl there is no friction
so its rotational kinetic energy will not change and remains the same
so it will have

now we know that


so we have




so the height on the smooth side is given as

Part b)
if both sides are rough then it will reach the same height on the other side because the energy is being conserved.
Part c)
Since marble will go to same height when it is rough while when it is smooth then it will go to the height

so on smooth it will go to lower height
<h3><u>Effects of the earths orbit around the sun:</u></h3>
The earth moves around the sun in an elliptical orbit, Johannes Kepler, a "German mathematician, and astronomer" described this elliptical orbit first. The orbit is close to being a circle but not a circle. Earth orbiting the sun mainly effects on seasons on earth.
Earth's four seasons are determined when Earth is tilted 23.4 degrees on the vertical axis, which is called as “axial tilt”. When a "southern hemisphere is tilted towards the sun", it experiences summer and northern hemisphere experiences winter, exactly opposite happens when northern hemisphere tilts towards Sun and this climate change goes on in all countries.