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An optical bench has 1.5 m long scale having four equal divisions in each cm. While measuring the focal length of a convex lens, the lens is kept at 75 cm mark of the scale and the object pin is kept at 45 cm mark. The image of the object pin on the other side of the lens overlaps with image pin that is kept at 135 cm mark. In this experiment, the percentage error in the measurement of the focal length of the lens is ____ .

Answer: 1.39% Solution: u = distance of the object from the lens u = - (75 -45) u = -30 cm v = distance of the image from the lens v = 60... View Article

Expand: (x-1)^3

Given expression: (x - 1)3Using the algebraic identity: (a - b)3 = a3 - b3 - 3ab(a - b)(x - 1)3 = x3 - 13 - 3(x)(1)(x - 1)= x3 - 1 - 3x(x - 1)=... View Article

Is 343 a prime number?

No, 343 is not a prime number. Reason: The number 343 has more than two factors, i.e. it has factors other than 1 and the number itself. Factors... View Article