2020년 4월 종로모의고사 영어영역 오답률 1위 해설강의

[고구마인생]

2020년 4월 종로모의고사 영어영역 오답률 1위 해설강의

Complete transfer of momentum does not happen when a nickel collides with a penny at rest, nor when a penny collides with a nickel at rest. The energy of the first, moving coin is only partially transferred to the second. (A) The nickel continues on its way, although more slowly. Only in the case of equal masses does the energy get completely transferred from one coin to the other; this is clear since for the nickel-penny collisions, both coins remain in motion. (B) That’s because they are not the same weight. If we make a line of coins, each coin becomes an agent of transfer of energy from left to right, if the first coin was traveling in that direction. A coin will impede the transfer of energy from its moving neighbor. (C) Two nickels are impedance matched; the stationary nickel stops the moving nickel dead. A penny and a nickel are impedance mismatched; a penny does not exert as much force back on the colliding nickel as another nickel would and does not decelerate the nickel all the way to zero speed. [3점] * nickel: 5센트 동전 ** impedance: 임피던스, 저항값(교류 회로에서 전압과 전류의 비율)