Problem 7E

What is wrong with the expression "That is just a theory," if by theory the speaker is referring to a scientific theory?

Solution 7E: (a) From figure, t he length of the pencil in the given picture is 7.5cm. According to the significant rules, the non zero digits are significant figures. Therefore, the measurement 7.5 cm has two significant figures. (b) From the figure, the automobile speedometer with inner face has shown speed in 72 mi/h. It has two significant figures.According to the significant rules, the non zero digits are always significant figures. On the other hand, the automobile speedometer with outer face has shown speed in 115 km/h. It has three significant figures.According to the significant rules, the non zero digits are always significant figures.