drafting and drawing compass with red line in circle form. engineering work tool. 3d illustration on the on white checkered sheet background. - 數學符號 個影片檔及 b 捲影像00:07
a female student successfully completes an equation on the smartboard for her class. - 數學符號 個影片檔及 b 捲影像00:17學生
a math teacher congratulates her student on successfully completing an equation. - 數學符號 個影片檔及 b 捲影像01:07
sun in orange sky, sunset, trees, branches & leaves in silhouette, male scientist writing equation underneath 'sub-solar surface', 'convection',... - 數學符號 個影片檔及 b 捲影像00:14日落
little boy playing with multi colored wooden block toys on the table at home. - 數學符號 個影片檔及 b 捲影像00:30
scientist woman writing formula on glass in laboratory research, problem solving or solution with tablet at night. serious, brainstorming and science, asian person with digital math and medical data - 數學符號 個影片檔及 b 捲影像00:17
presents interviews with four scientists who explore their thought processes, personalities, and methods of work as they analyze ways by which they... - 數學符號 個影片檔及 b 捲影像00:35
electrons at work - part 20 of 22. electrons carry electric charges; they have mass and can move objects by colliding with them. visual evidence that electrons can be found in all kinds of materials is given when a hairbrush rubbed on a cat attracts a ban - 數學符號 個影片檔及 b 捲影像00:31
magnetic, electric and gravitational fields - part 3 of 19. evidence of the magnetic field is illustrated by bringing a compass close to a magnet and watching the compass needle. further evidence of an electric field is demonstrated by rubbing a plastic r - 數學符號 個影片檔及 b 捲影像00:29
unrecognizable person holding a smart transparent screen showing growth percentages, temperature and information at a lettuce crop - 數學符號 個影片檔及 b 捲影像00:04
female student solving mathematical sum on whiteboard by teacher in classroom - 數學符號 個影片檔及 b 捲影像00:26初中, 初中學生
school student writing math answer on white board and solving mathematic problem during education and academic class. secondary or junior pupil learning and answering timetables question in classroom - 數學符號 個影片檔及 b 捲影像00:09
intelligent businessperson copies an equation on to a whiteboard in the office - 數學符號 個影片檔及 b 捲影像00:08
1940s black and white medium shot calculus professor standing in front of chalkboard covered with equations / students sitting before him / audio - 數學符號 個影片檔及 b 捲影像00:06白人
1985 animation red image of albert einstein with ""e=mc"" appearing next to his head - 數學符號 個影片檔及 b 捲影像00:09
teacher teaching mathematics on large tv screen to adult students in classroom - 數學符號 個影片檔及 b 捲影像00:11
focused businessperson writes formulas on a glassboard while talking with coworkers - 數學符號 個影片檔及 b 捲影像00:26
4k video footage of two scientists solving equations on a glass screen in a laboratory - 數學符號 個影片檔及 b 捲影像00:17
