5
א. הגופים מתנגשים על משטח אופקי וחלק. בזמן ההתנגשות תנועת הגופים מושפעת רק מכוחות פנימיים,
לכן בזמן ההתנגשות התנע נשמר.
נכתוב את משוואת שימור התנע ונחשב מהמשוואה את מהירות הגופים U .
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ב. לאחר ההתנגשות הגופים נעים במהירות שלילית , הם נעים נגד כיוון הציר, שמאלה.
ג. נחשב את גודל המתקף שהפעיל גוף 1 על גוף 2 בעזרת משפט התנע מתקף.
המתקף שהפעיל גוף 1 על גוף 2 שווה לשינוי בתנע של גוף 2:
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המתקף הוא שלילי מכיוון שגוף 1 מפעיל על גוף 2 כוח בכיוון הפוך לכיוון הציר.
ד. נחשב את גודל המתקף שהפעיל גוף 2 על גוף 1 בעזרת משפט התנע מתקף.
המתקף שהפעיל גוף 2 על גוף 1 שווה לשינוי בתנע של גוף 1:
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