natural 1 Forces We cant see forces but we can feel their effect . - - PDF document
12/03/2020 natural 1 Forces We cant see forces but we can feel their effect . Forces make things: move or stop change shape break fall to the ground stay still float or sink 2 1 12/03/2020 Forces can be PUSH OR
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We can’t see forces but we can feel their effect. Forces make things:
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PUSH OR PULL CONTACT AND NON-CONTACT BALANCED OR UNBALANCED
Magnets create a magnetic field around them. This force attracts objects made of iron and steel. This is a photo of a magnet and iron filings. The iron filings show us where the magnetic field is.
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Opposite poles attract. Same poles repel.
Gravity is a non-contact, pull force. All masses have gravity. It is a force that pulls towards their centre. This force is only noticeable with very large masses, for example, planets. The Earth’s gravity pulls everything on or near the Earth towards its centre. This stops us and our belongings floating away!
Newton discovered gravity. 5 6
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Weight is the force with which we are attracted to the ground. It depends on: GRAVITY (N) and
[weight = mass x gravity]
Upthrust is a contact, push force applied by water and air. It pushes objects in air and water up. The bigger the VOLUME, the bigger the upthrust.
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GRAVITY UPTHRUST HOW do you think GRAVITY and UPTHRUST need to be?
Upthrust needs to be as strong as gravity!
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