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Question
A bullet fired against a window glass pane makes a hole in it without any cracks while a stone striking the same glass pane smashes it; explain with reason.
Solution
When the bullet strikes the glass, the part of the glass coming in contact with the bullet immediately shares the large velocity of the bullet and makes a hole in it while the rest of the glass pane, due to the inertia of rest, remains at rest and so is not smashed. But when a stone strikes the same glass pan, the surrounding part of the glass gets time to share the comparatively low velocity of stone and so it is smashed.
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