Physics

NEET PHYSICS TEST ARRANGEMENT: QUESTION: A capillary tube of radius 'r'   is immersed in water and the water rises it to a height h.The mass of the water in the capillary tube is 5 g. Another capillary tube of radius '2r' is immersed in water.The mass of the water   that will rise in the tube is; [A].     2.5 g [B].     5.0 g [C].   10.0 g [D].   20.0 g ANSWER: ANSWER - [C] SOLUTION: CAPILLARY RISE: A capillary tube (glass tube) of radius 'r 'is dipped in water, the surface pulls the capillary walls in downward direction. Capillary walls pull the surface in upward direction. By the way the water in the tube will rise above the adjacent liquid level till the forces get balanced. This rises what we called it as capillary rise WHAT ARE THE TWO FORCES ACTING AT EQUILIBRIUM? 1.      First one is the weight of the water column, acting downwards.              Weight of the water in the column = mass x gravity                                                        

NEET PHYSICS TEST ARRANGEMENT: QUESTION: A body weighs 72 N on the surface   of the earth.What is the gravitational force on it, at a height equal to half the radius of the Earth. [A]     48 N [B]     32 N [C]     30 N [D]     24 N ANSWER: ANSWER - [B] SOLUTION: GRAVITATIONAL FORCE: Earth’s gravity comes from all its mass. All its mass makes a combined gravitational pull on the mass of other body. Objects with more mass have more gravity. Gravity gets weaker with distance.  That is given by the Newton’s universal law of gravitation which states that ‘Every  body on the universe attracts every other body with a force which is directly proportional to the product of their masses and inversely proportional to  the square of the mean distance between them’. EXAMPLES: The gravitational pull on the moon pulls the seas towards it causing the ocean tides. The sun’s gravity keeps earth in orbit around it. GRAVITATIONAL  FORCE AT A HEIGHT EQUAL TO HALF THE RADIUS OF THE EARTH: ALITER

POTENTIOMETER EXPERIMENT- INTERNAL RESISTANCE OF A PRIMARY CELL CIRCUIT DIAGRAM : AB-     Potentiometer Rh-Rheostat L  - Lechlanche cell H.R-High resistance G- Galvanometer R-Known Resistance J- Pencil Jockey positions Bt -Battery Eliminator (3 amps.) K- Plug keys SIMPLE CIRCUIT DIAGRAM EXPERIMENTAL SET UP FORMULA TABULAR COLUMN & OBSERVATION: PROCEDURE:     The circuit connections and the experimental set up are made as shown in the previous page.       In the open circuit,when resistance is not included, the emf of the cell is deterimned by noting the balncing length.       In the closed circuit, when the resistance is included the balncing length is to be noted.       The experiment is r epeated fo r different  values  of R and the readings are tabulated.     Using the formula the internal resistance of the given cell can be calculated . RESULT:                The internal resistance of the given               primary  cell (Lechlanche cell)  =  7.16  Ohms

NEET PHYSICS TEST ARRANGEMENT:  #5 QUESTION: A coil of radius R rotating about a diametric axis with angular velovity ω in a uniform magnetic field B.Find the value of the maximum voltage developed. Radius R=10 cm and   B= 5x10 -5 T. For half rotation it takes a time of 0.2 sec.                          A.        3x10 -5 V                              B.         2.5x10 -5 V                               C.         5x10 -6 V                                             D.          5x10 -5 V         ANSWER:                                 ANSWER - B.        SOLUTION:           MAGNETIC FLUX LINKED WITH THE COIL:       INDUCED EMF: MAXIMUM VOLTAGE DEVELOPED:          

NUMERICALS ON KIRCHHOFF'S LAW: Calculate the current through the galvanometer when a potential difference of 10 V is maintained across AC as shown in the image. SOLUTION: KIRCHHOFF'S SECOND LAW: Kirchhoff's subsequent(second) law is otherwise called Voltage law (OR) Loop law.This law depends on LAW OF CONSERVATION OF ENERGY.Kirchhoff's subsequent law expresses that " THE ALGEBRAIC SUM OF ALL THE POTENTIAL DIFFERENCES ALONG A CLOSED LOOP IS ZERO". CONVENTIONS: Accept any course (direction) as the heading of traversal (direction of traversal). (Either clockwise or anticlockwise) EMF of the cell is POSITIVE in the event that the bearing of the crossing (direction of the traversal) is from its NEGATIVE terminal to POSITIVE terminal. (NPP) EMF of the cell is NEGATIVE assuming the heading of the crossing (direction of the traversal) is from its POSITIVE terminal to NEGATIVE terminal of the battery. (PNN) The IR item is taken as POSITIVE on the off chance that the

PHYSICS NEET TEST ARRANGEMENT: QUESTION: Light of frequency 1.5 times the threshold frequency is incident on a photosensitive material.What will be the photoelectric current, if the frequency is halved and the intensity is doubled?                 A.       Doubled               B.        Four times               C.        One-fourth               D.        Zero ANSWER :                                                                                        ANSWER - D. SOLUTION: Reason: No photoelectric emanation will happen on the off chance that the frequency of the occurrence light is underneath the threshold frequency. The quantity of electrons radiated each second (Photoelectric flow) is relative to the intensity of incident light Kinetic energy increments with expansion in frequency over a threshold value. The greatest speed of the photoelectrons relies upon the frequency of the incident light. light. PHOTOELECTRIC EFFECT: The photoelectric effect includes lighting a metal surfac

COMPOUND MICROSCOPE: Compound microscope is a microscope uses the mix of two lenses to deliver a higher magnification.it is utilized in labs and principally utilized for the examination purpose.The absolute amplification created by a compound microscope not entirely settled by duplicating the amplification of the two lenses (objective and eye piece  lens) CONSTRUCTION: There are two lenses joined in a compound magnifying instrument (microscope) which permits a lot higher amplification. The compound magnifying instrument (microscpe) comprises of a long barrel shaped cylinder where one finish of the cylinder has an objective lens (small aperture and small focal length) and the opposite end has an eyepiece lens (the aperture and the focal  length are fairly bigger than the objective lens). Objective lens which centers a genuine picture of the object,the picture is additionally amplified by the eyepiece which gives the watcher a picture that is virtual, amplified and reversed (inverted) co

PHYSICS NEET TEST ARRANGEMENT #3 QUESTION: 1.      A screw gauge has a least count of 0.01 mm, there are 50 divisions in its circular scale,  then the pitch of the screw is…………                                 A.        0.01 mm                                 B.        0.25 mm                                 C.        0.5  mm                                 D.        1.0  mm ANSWER:                           ANSWER : C SOLUTION: As per question the least count of the screw gauge is 0.01 mm, total number of divisions on its circular scale is 50. Least count of any instrument is the littlest division that can be estimated utilizing the instrument.              pitch = Least count X  total number of divisions in the                                                        circular scale              Pitch of the screw = 0.01 mm X 50              Pitch of the screw = 0.5 mm