Recently Active Physics Questions

We know that electric current is not a vector. Then in Kirchoff's law,why do we take negative value of current from our calculations to have a direction opposite to the assumed direction? ...

Q.) 3 insulated conducting spheres A, B and C of radii a, b, c respectively (a<b<c) has charges q1, q2, q3 respectively. Find their- (i) potentials (ii) the reduction in the potential of the outermost sphere when the in ...

well i had some doubts.......... the first one isn't really a study doubt....its a general query that came to my mind while reading abt the earth's magnetism.. as we know that the earth reverses both the magnitude as well as ...

someone pleaz answer these ques.... 1) A bal is thrown vertically up wards. It is observed at a height h twice with a time interval t. The initial velocity of the ball is....... 2)A circus artist maintains 4 balls in motion . ...

electrically charged drops of mercury fall from altitude h into a spherical metal vessel of radius R. in the upper part of which there is a small opening. The mass of each drop is m & charge is Q.What is the number 'n' of las ...

In NCERT books,it is written that electron was discovered in 1859. Ohm's law was given before 1854 because Ohm died in 1854 and Coulomb' law was given before 1806 because coulomb died in 1806.We know that electron flow is kno ...

1)Can anybody please explain me the various methods for finding the equivalent resistence in a given ckt.m having a lil bit prob in this .....i just only noe the simple methods like of pointing out the same potential points,K ...

the last post i posted was wrong due to my superb english on net n my failure to reply due to my xams so now whenever we calculate magnetic field due to a solenoid or a wire from amperes law or the same by gaus law for differ ...

we say that conductors r called so coz they have lot of free electrons , which r generated coz in conductors electrons r loosely held and in insulators they r tightly held so no free electrons........ my quesn is that why is ...

hc verma magnetic field due 2 current ques:5 &6 .plzzzz anyone hlp............. urgent;;;; ...

solve hcverma ch-10 Q15 and 17 ...

if we say tht an electron consist of two parts then each part will be having -ve charge so they must repel each other.....so the electron must break in those parts but this not in real then which force does keep the parts of ...

A particle slides at constant speed in a horizontal circular path on the frictionless inner surface of an inverted right circular cone. How is the particle’s kinetic energy related to its potential energy ...

A semicircular ring of mass m is kept in x-y plane with centre at origin.It is charged in such a way such that charge/unit length varies as λ=λocosθ . Find accelration of ring when electric field E=Eoxi+Eoj is switched on. ...

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A car travelling at 60 Km/h overtake another car travelling at 42Km/h .Assuming each car to be 5.0m long,find the tame taken during the overtake and the total road distance used for the overtake ...

a stunt man jumps his car over a crater (neglect air resistance ) then during the whole flight the driver experiences weightlessness .Why???? ...

A rubber band with initial length L has one end tied to a wall. At t = 0, the other end is pulled away from the wall at speed V (assume that the rubber band stretches uniformly). At the same time, an ant located at the end no ...

a healthy young man standing at a distance of 7m from a 11.8 m high building sees a kid slipping from the top floor . with what speed (assumed uniform ) should he run to catch the kid at an arm height (1.8m) ...

if a person is walking in south direction with a speed of 20 m/s and in that time the direction of the wind ne direction and if the person increases the speed and walking with a speed of 40m/s then the direction of wind will ...

a ball is dropped from a height of 5m onto a sandy floof and penentrates the sand upto 10 cm before coming to rest . find the retardation of the ball in sand assuming it to be uniform. ...

1)The metre is defined as the distance by travelled light in 1/299,792,458 second. Why didn't people choose some easier number such as 1/300,000,000 second? Why not 1 second? 2)Suppose you are told that the linear size of eve ...

A person sitting on the top of a tall building is droping ball at regular intervals of one seconds .Find the position of 3rd,4th,and5th ball when the sixth ball is being dropped. ...

I couldn't solve this.- Rain is falling vertically with a speed of 30m/s.A woman on a bicycle is travelling with a speed of 10m/s in the north to south direction.In what direction should she hold her umbrella in order to prot ...

1.find the condition that the root of the equation ax^2+bx+c=0 may differ by 5. 2.if the equation x^2+px+q=0 and x^2+p'x+q'=0 have a common root ,show that it must be equal to pq'-- p'q/q--q' or q--q'/p'--p ...

An NCC is going at a uniform speed of 6 Km/hr through a place under a berry tree on which a bird is sitting at height of 12.1m. At a particular instant the bird drop a berry . Which cadet (give the distance from the tree at t ...

in a soccer practice session the football is kept at the centre of the field 40yards from the 10ft high goalpoast. a goal is attempted by kicking the football at a speed of 64ft/s at an angle of 45° to the horizontal. will t ...

In d Modern Physics chapter in our syllabus(ICSE X), under d Beta emission heading i found something called "anti-neutrino". wud nyone plz say wat is dat. ...

A piece of metal of 2kg-wt is suspended from one end of a vertical wire whose end is fixed and the piece is fully immersed in an oil od density 0.7*1000 kg/m3 .The length of the wire increases by 1mm.If the diameter of the wi ...

1.Three particles are situated at 3 vertices of a triangle ABC of side a.Each particle moves with a speed v such that A moves towards B, B towards C and C towards A.Find the trajectory of the the particles. ...