if least count is 10kg then 8×10^3kg has how many significant figures?
Answers
Answer ⇒ 3.
Explanation ⇒
Now, this instrument which is measuring the mass of the body as 8 × 10³, has an least count of 10 kg.
While calculating no. of significant figures, it is always noted that power of ten is never counted.
Thus, ignoring power of 10, there is only 1 number, hat is 8.
Hence, the no. of significant figure in the given case is 1.
But Listen!!!.
Least count have been given here.
Least count means the smallest possible measurement that can be given by the instrument.
Thus, we know that the no. of figures which have uncertainty is just one.
Thus, Whole powers of 10 are not uncertain.
∴ 8 × 10³ g = 8000 kg.
Now, least count is 10 kg, thus there will be an error in 10 kg only.
∴ mass wil either be 7990 kg or 8010 kg.
Now, By the definition of the significant figures, those no. will be significant which are accurately measured.
Hence, there is only problem in last one digits, due to 10 kg.
Thus, there are three significant figures in the given case.
Hope it helps.