Một lượng khí oxy khối lượng 160g được nung nóng từ nhiệt độ 50ºC đến 60ºC. Tìm nhiệt lượng mà khi nhận được và độ biến thiên nội năng của khối khí trong hai quá trình: a. Đẳng tích
b. Đẳng áp

Amethod of procedure that has characterized natural science since the 17th century, consisting in systematic observation, measurement, and experiment, and the formulation, testing, and modification of hypotheses.

Year  1936,  lehman predicted that the earths 'inner core' is solid. she observed that the seismic signals during her study were bent and did not pass through instead bouncing back. later it was confirmed that the earth's inner core was solid made up of nickel-iron and had a molten outer core.