How does gravity affect objects

How does gravity affect objects in our universe? May 18, Gravity is what keeps everything together and from flying off. Explanation: Just like the sun 's gravity keeps the solar system's planets in orbit, so too does the gravity of the galaxy keep all the stars in tow. Related questions Does gravitational force get weaker with distance?

How strong is gravitational force? A gravity force acts on an object regardless of whether it is moving or not moving. In everyday situations, the size of the gravity force on something does not change significantly as it rises above the Earth.

An object needs to go much higher than a jumbo jet for major differences to occur. The gravity force on an object from the Earth is the same regardless of whether the object is surrounded by air or water or anything else.

It is helpful if students understand that the Earth and other planets orbit the sun, and that when things change direction as the planets are constantly doing they have a force on them. This idea is also developed in the focus ideas Pushes and pulls ; What is a force? The idea that there must be a force on the planets that changes their direction can be linked to the gravity force of the Earth on objects near its surface, thus helping students to understand the generalisation that gravity forces exist everywhere in the universe.

POE Predict-Observe-Explain : a spring balance with a weight attached hangs inside a sealed bell jar connected to a vacuum pump. Ask students to predict whether, and how, the spring balance reading will change when the air is pumped out.

Then ask them to explain their observations. Note: It is helpful to show beforehand that the reading registers a reduction in a net downward force if the weight is placed in water due to the upward push of water.

See the diagrams. Well, the answer is that the moon IS falling; all the time, but doesn't get any closer to us! Remember that if there wasn't a force acting, the Moon would be traveling in a straight line.

Because there IS a force of attraction toward the Earth, the moon "falls" from a straight line into a curve orbit around the Earth and ends up revolving around us. The Earth's gravity holds it in orbit, so it can't just go off in a straight line. Think about holding a ball on a string and spinning it in a circle. If you were to cut that string no more gravity , the ball would fly off in a straight line in the direction it was going when you cut the string.

That direction, by the way, is not directly away from your hand, but tangent to the circle. Tangent is a geometry term used to describe a direction that are related to the slope of a curve. Math stuff. The pull of the string inward toward your hand is like the Earth's gravitational pull inward toward the center of the Earth.

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