Tìm hiểu giá điện thực tế. Tính lượng điện năng tiêu thụ trong tháng 10 của gia đình em theo đơn vị J (có chụp ảnh hoá đơn )

if the thermos has a vacuum innner, then heat through conv currents and conduction are reduced = vacuum flask

the body's situation won't change the forces are equal opposit and on the same body

photocells convert light energy to electricity

when two balls of the different masses are dropped from equal height, they reach the ground at the same time .this is because they experience the same acceleration.

the acceleration is independent of mass.

thus when they are dropped they will always maintain the same velocity and travel the same distance (neglect air resistance of course) at the same time.