An artificial satellite orbiting around the Earth does not fall down. This is so because the attraction of Earth
- Adoes not exist at such distance
- Bis neutralized by the attraction of the moon
- Cprovides the necessary speed for its steady motion
- Dprovides the necessary acceleration for its motionCorrect
Explanation
The correct answer is D because the gravitational pull of the Earth acts as a centripetal force on the satellite. This force continuously changes the direction of the satellite's velocity, which is a form of acceleration. Rather than pulling the satellite down to the surface, this acceleration keeps it constantly falling toward Earth while moving sideways fast enough to follow the curve of the planet, maintaining its circular or elliptical orbit.
Option A is incorrect because gravity exists even at great distances. Option B is incorrect because the moon's gravity is too weak to neutralize Earth's pull on a nearby satellite. Option C is incorrect because gravity provides the force for the orbital path, not the initial speed required to reach orbit.
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