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Push and pull forces part 4. So far we've seen types of push and pull forces. Do you remember

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all of them? Let's review. First we have contact and non-contact forces. Number two,

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balanced and unbalanced forces and number three magnetism the fourth type

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of push and pull force is gravity gravity is a non-contact force that

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pulls objects towards the center this force is only noticeable with very large

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objects for example planets large objects have a stronger pull toward

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center than smaller objects. Earth is six times bigger than the moon. This means

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that the force of gravity on Earth is six times greater than the force of

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gravity on the moon. Now let's talk about mass and weight. Mass is the amount of

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matter in an object it is measured in kilograms weight is a force and its unit of measurement

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is in newtons let's imagine that this dog has a mass of 10 kilograms

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its mass is the same on earth and on the moon because the matter does not change

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The dog weighs 100 Newtons on Earth and 16 Newtons on the Moon. This is because weight

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is a force, which is mass multiplied by gravity. The dog weighs more on Earth

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because Earth has stronger gravity. Until next time, see you soon!