Acceleration of gravity is proportional to 1/D² .
('D' is the distance from the Earth's center.)
We need (D / R)² = 9.8
('R' is the Earth's radius.)
D/R = √9.8 = 3.13
Distance from Earth's <u>center</u> = 3.13 R
Distance above Earth's <u>surface</u> = 2.13 R = about 13,570 km =====================================================
<span>Accelerarea de gravitate este proporțională cu 1 / D².
('D este distanța de centrul Pământului.)
Avem nevoie de (D / R) ² = 9,8
('R' este raza Pământului.)</span><span>
D / R = √9.8 = 3,13
Distanța de la <u>centrul</u> Pamantului = 3,13 R
Distanța de deasupra <u>suprafetei</u> Pamantului = 2.13 R = aproximativ <span><em>13,570 km</em></span></span>
Answer:
60m/s
Explanation:
initial energy = final energy
g.p.e = k.e
k.e = 0.5 × mass × velocity²
g.p.e = 990000J as per Question
990000Nm = 0.5 × 550 × V²
V² = 3600
V = 60m/s
Gamma radiations do not reach the surface of the Earth
Explanation:
Sun radiates all of these radiations but one of them does not reach the surface of the Earth. Most of the radiation switch reaching the Earth's surface are visible and infrared radiations.
I believe the answer here is A, renewable energy sources are resources that the earth give that can be replenished whither it be within a few days to a year; a prime example of a renewable energy source would be the sun or even the wind, it's constantly being renewed no matter how much of it we use.
I hope this helps you out a little bit!
If the sign of work is negative, that means the force and the motion are in opposite directions.
Let's say you see something roll off of the shelf. You catch it, and you let it down slowly and gently.
Gravity exerted down-force on it and it moved down. Gravity did positive work on it.
YOU exerted UP-force on it and it moved down. YOU did negative work on it.
(Also, the falling object exerted down-force on your hand, and your hand moved down. The falling object did positive work on your hand ! Where did THAT energy come from ? It came from the potential energy that the object had while it was on the shelf. Your hand absorbed that energy on the way down, doing negative work. So the object didn't have any kinetic energy when it reached the floor, and it did NOT splinter the floor or shatter in smithereens. It had barely enough energy left to make a sound when it hit the floor.)
