Вопрос школьника по предмету Физика
Самоделкин скрепил последовательно две пружины равной длины. Растягивая свободные концы получившейся конструкции, он заметил, что первая пружина удлинилась на 5 см, а удлинение второй оказалось равным 1 см. Какова жёсткость второй пружины, если жёсткость первой – 100 Н/м? Ответ ввести в Н/м с точностью до целых.
Ответ учителя по предмету Физика
Вычислим силу, с которой действуют на первую пружину. F=kΔl 5 см=5/100=0.05 (м)
F=100*0.05=5 (Н)
Эта же сила действует и на другую пружину. Вычислим жесткость k1=F/Δl1 1 см=1/100=0.01 (м) k1=5/0.01=500 (Н/м)
Ответ: 500 Н/м
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