A compound microscope forms an inverted image of an object. In which of the following cases it is likely to create difficulties? a. Looking at small germs. b.Looking at circular spots. c. Looking at a vertical tube containing some water.

Flow cytometry, illustrated in the figure, is a technique used to sort cells by type. The cells are placed in a conducting saline solution which is then forced from a nozzle. The stream breaks up into small droplets, each containing one cell. A metal collar surrounds the stream right at the point where the droplets seprate from the stream. Charging the collar polarizes the conducting liquid, causing the droplets to become charged as they break off from the steam. A leser beam probes the solution just upstream from the charging collar, looking for the presence of certain types of cells. All droplets containing one particular type of cell are given the same charge by the charging collar. Droplets with other desired types of cells receive a different charge, and droplats with no desired cell receive no charge. The charged. The charges droplets then pass between two parallel charged electrodes where they receive a horizontal force that directs force that directs them into different collection tubes, depending on air charge.

Flow cytometry, illustrated in the figure, is a technique used to sort cells by type. The cells are placed in a conducting saline solution which is then forced from a nozzle. The stream breaks up into small droplets, each containing one cell. A metal collar surrounds the stream right at the point where the droplets seprate from the stream. Charging the collar polarizes the conducting liquid, causing the droplets to become charged as they break off from the steam. A leser beam probes the solution just upstream from the charging collar, looking for the presence of certain types of cells. All droplets containing one particular type of cell are given the same charge by the charging collar. Droplets with other desired types of cells receive a different charge, and droplats with no desired cell receive no charge. The charged. The charges droplets then pass between two parallel charged electrodes where they receive a horizontal force that directs force that directs them into different collection tubes, depending on air charge. Another way to sort the droplets would be to given each droplet the same charge, then vary the electric field between the deflection plates. For the apparatus as sketched, this technique will not work because

A small ball of mass m and charge q is attached to the bottom end of a piece of negligible mass thread of length l, whose top end is fixed. The system formed by the thread and ball is in vertical plane and is in uniform horizontal magnetic field B, which is perpendicular to the plane of figure and points into the paper The ball is started with a velocity v_(0) from lower most point of circle in a direction perpendicular both to the magnetic induction and to direction of thread. The ball moves along a circular path such that thread remains tight during the whole motion. Neglect any loss of enery. By what factor is the force acting on the thread (tension in thread) at point A is greater than at point C, when speed of the ball is the above stated one?

One hard and stormy night you find yourself lost in the forest when you come upon a small hut. Entering it you see a crooked old woman in the corner hunched over a crystal ball. You are about to make a hasty exit when you hear the howl of wolves outside. Taking another look at the gyspy you decide to take your chances with the wolves, but the door is jammed shut. Resigned to a bad situation you approach her slowly, wondering just what is the focal length of that nifty crystal ball. The old lady moves the crystal ball closer to her wrinkled old face. At some point you can no longer get an image of her . At what object distance will there be no change of the gypsy formed?

A bird in air is diving vertically over a tank with speed 5 "cm//s" , base of tank is silvered. A fish in the tank is rising upward abong the same line with speed 2cm/s. Water level is falling at rate of 2cm/s [Take : mu_(water) = 4//3 ] {:("Column"I(cm//s), "Column"II), ((A) "Speed of the image of fish as seen by the bird directly", (P) 8), ((B) "Speed of the image of fish formed after reflection in the mirror as seen by the bird", (Q) 6), ((C) "Speed of image of bird relative to the fish looking upwards" , (R) 3), ((D) "Speed of image of bird relative to the fish looking downwards in the mirror" , (S) 4):}

Bottles containing C_(6)H_(5)I and C_(6)H_(5)-CH_(2)I lost their original lables. They were labelled A and B for festing. A and B were separately taken in a test tube and boiled with NaOH solution. The end solution in each tube was made acidic with dilute HNO_(3) and then some AgNO_(3) solution was added. Substance B gave a yellow precipitate. Which one of the following statements is true for this experiment.