Title: אופציונלי

Text: Consider a force like gravitation which varies predominantly inversely as the square of the distance, but which is about a billion-billion-billion-billion times stronger. And with another difference. There are two kinds of "matter," which we can call positive and negative. Like kinds repel and unlike kinds attract - unlike gravity where there is only attraction. What would happen? כל פסקה תהיה מבחן.

Save test: השתמש בזה אם אתה רוצה לשתף את המבחן הזה בהקלדה (רק למשתמשים מאומתים).