Land: Tectonic plate movement under the Earth can create landforms by pushing up mountains and hills. Erosion by water and wind can wear down land and create landforms like valleys and canyons. ... Landforms can exist under water in the form of mountain ranges and basins under the sea.
Atmosphere: (4.6 billion years ago)
As Earth cooled, an atmosphere formed mainly from gases spewed from volcanoes. It included hydrogen sulfide, methane, and ten to 200 times as much carbon dioxide as today's atmosphere. After about half a billion years, Earth's surface cooled and solidified enough for water to collect on it.
Ocean: After the Earth's surface had cooled to a temperature below the boiling point of water, rain began to fall—and continued to fall for centuries. As the water drained into the great hollows in the Earth's surface, the primeval ocean came into existence. The forces of gravity prevented the water from leaving the planet.
J.J. Thomson discovered electrons and noticed that an atom can be divided. Also, he concluded atoms are made of positive cores and negatively charged particles within it.
Answer:
Explanation:
For a body on a ramp with mass m, the forces acting on the body along the vertical component are the weight and the normal reaction.
The weight of the body acts in the negative y direction while the normal reaction acts in the positive y direction
Taking the sum of forces along the y component
Sum Fy = -W+R = ma
Since acceleration is zero
-W+R = m(0)
-W+R = 0
-W = -R
W = R
Hence the Normal reaction force acting on the on the body is equal to normal force
It's Decrease or cease to exist, but I'm leaning more towards decrease.
Answer:
Required mass of sand is 20 kg
Explanation:
Given:
Mass of the plank = 25 kg
Distance of the Center of gravity of the Plank from the fulcrum = 
Distance of the Center of gravity of the sand box from the fulcrum = 
Balancing the torque due to the plank and the sand box with respect to the fulcrum
Torque = Force × perpendicular distance
thus, we get
(25 × g) × 0.5 = weight of sand × 0.625
where, g is the acceleration due to gravity
or
(25 × g) × 0.5 = (mass of sand × g) × 0.625
or
mass of sand = 20 kg
<u>Hence, the required mass of the sand is </u><u>20 kg</u>
