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प्रश्न
Give two examples each of contact and non-contact forces.
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उत्तर
Contact Forces:
(i) Pushing a pile of rubble by a bulldozer.
(ii) Squeezing of a gum tube to extract the gum.
Non-contact Forces:
(i) When a magnet is brought near iron-nails, they stick to the magnet.
(ii) A ripen apple falls by itself from the tree.
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