một vận động viên đi xe đạp thực hiện một cuộc đua trên một quãng đường dài 72km. đoạn đường đầu dài 45km hết 3 giờ .đoạn đường thứ còn lại chạy hết 1 giờ 30 phút . tính vận tốc trung bình của vận động viên này trên từng đoạn và trên cả đoạn đường

Look at the potential energy diagram for a chemical reaction. which statement correctly describes the energy changes that occur in the forward reaction?

Which of the following statements is true about women and minorities in early psychology? a. in the early 20th century, numerous graduate schools recruited women and minorities to study psychology. b. opportunities in higher education were limited for women and minorities in the early 20th century due to discrimination. c. despite some obstacles, there were numerous employment opportunities for women and minorities. d. women and minorities were often selected to do academic research in an effort to make the field more diverse.

Two 1.20-m nonconducting wires meet at a right angle. one segment carries + 2.50 µc of charge distributed uniformly along its length, and the other carries - 2.50 µc distributed uniformly along it, as shown in fig. 21.50. ( a. find the magnitude and direction of the electric field these wires produce at point p, which is 60.0 cm from each wire. ( b. if an electron is released at p, what are the magnitude and direction of the net force that these wires exert on it?