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Simplify root 45

Root 45 means square root of 45. I.e.,√45 Square root of 45 can be simplified as follows: √45 = √(9×5) √45 =... View Article

A lady went shopping and spent half of what she had on buying hankies and gave a rupee to a beggar waiting outside the shop. She spent half of what was left on lunch and followed that up with a two rupee tip. She spent half of the remaining amount on the book and three rupees on bus fare. When she reached home, she found that she had exactly one rupee left. How much money did she start with?

Assume that the lady started with Rs. x. At shopping, she spent half of what she had. Hence, x/2. Therefore, remaining = x/2. She gave Rs. 1... View Article

An infinite line charge of uniform electric charge density λ lies along the axis electrically conducting an infinite cylindrical shell of radius R. At time t=0, the space in the cylinder is filled with a material of permittivity ε and electrical conductivity σ. The electrical conduction in the material follows Ohm’s law. Which one of the following best describes the subsequent variation of the magnitude of current density j(t) at any point in the material?

a) b) c) d) Solution: Option d) describes the subsequent variation of the magnitude of current density j(t) at any point in the material.... View Article

When a piece of wire is held diametrically in a screw gauge [pitch =1mm, number of division on circular scale =100], the readings obtained are as shown. Now, if we measure the same with the help of vernier callipers [1MSD=1mm,10 divisions of vernier coinciding with 9 divisions of main scale] having a negative zero error of 0.5mm, then which of the following figures correctly represents the reading?

a) b) c) d) Solution: Option a) is the correct answer since the values match with the value of screw gauge reading.... View Article