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Class 11
Physics
Unit & measurment
a physical quantity p is related to four observabl...

Question:
A physical quantity P is related to four observables a, b, c and d as follows :

The percentage errors of measurement in a, b, c and d are 1%, 3%, 4% and 2%, respectively. What is the percentage error in the quantity P ? If the value of P calculated using the above relation turns out to be 3.763, to what value should you round off the result ?

Answer:

= 3x1 +2x3 + ½ x 4 + 2

= 3 + 6 +2 + 2

= 13 %

Percentage error in P = 13 %

Value of P is given as 3.763.

By rounding off the given value to the first decimal place, we get P = 3.8.

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