Basic Physics Questions and Answers

rent carrying loop is placed in a plane perpendicular to a long current carrying wire as shown A Force on the loop is attractive

le between PMT 50 5 Questions asked prior to Medical Ent Exams 2005 36 A boat is sent across a river with a velocity of 8 km h If the resultant velocity of the boat is 10 km h then velocity of the river is rpendicular to the 1 8 km h 2 10 km h alue of a is 3 12 8 km h 4 6 km h MT Prelims 2005 27 Which of the following is correct relation between Prelims 2006 C 3 4 43 Two racin in circles speeds circle in speeds 1 4

57 4 0 15 T The magnetic field between the plates of radius 12 cm separated by a distance of 4 mm of a parallel plate capacitor of capacitance 100 pF along the axis of plates having conduction current of 0 15 A is 1 zero 2 1 5 T 3 15 T From NCERT

The equilibrium potential of sodium in an axon is equal to 58 mV at the body temperature Determine the intracellular concentration of sodium if the extracellular concentration is 510 mM Select one

37 The position time x f graph of a particle moving along x axis is shown Average speed of the particle in time interval t 0 to t 20 s is x m 20 10 1 Zero 2 1 m s 3 2 m s 4 4 m s 6 B t 0 8 10 12 16 20 t s

the ends A and B ofe running e boy at B starts r to AB with velocity v g simultaneously with other boy in a timet PMT Prelims 2005 v v a V A and B is is equal to Prelims 2005 NEET 41 Two particles A and B are connected by a rigid rod AB The rod slides along perpendicular rails as shown here The velocity of A to the left is 10 m s What is the velocity of B when angle 60 A 1 10 m s 2 9 8 m s 3 5 8 m s 4 17 3 m s 42 The speed of a boat is 5 km h in still water It crosses a river of width Motio 46 If B A B then and B will be 1 90 3 0 2 4 47 A particle moves along a c with constant tangential acc of the particle is 80 m s at revolution after motion ha acceleration is 1 40 m s 3 160 m s

integer Q 12 A loop of radius 1 m is made from string and this loop is slid on the surface of sphere of radius 2 m Sphere along with loop rotates about its axis with a constant angular velocity w rad s Assuming that loop does not slip on the sphere If tension in the loop in S l units is Find n There is no friction between the loop and spherical surface Given mass per unit length of th loop is kg m w 2 3 rad s and g 10 m s 2m Save R

Match the following recurrence relations with their complexitie 1 T n T n 2 O 1 2 T n 2 T n 2 0 1 3 T n 2 T n 2 O n 4 T n T n 1 O n a O n b O n log n c O log n d O n

3 class NumberSystem int naturalNumbers 4 String Characters 5 6 7 8 this would be invoked while an object of that class is created NumberSystem System out println Constructor called

A plastic sphere of radius r floats almost fully submerged in a liquid as shown in the figure Density of the liquid is P acceleration of free fall is g The force exerted by the liquid on the lower half of the sphere excluding

Q 13 to Q 15 Consider a particle of mass m moving in a vertical circle by a string of length 1 under the influence of gravity of earth B Let A is the lowest point of trajectory and AC and BD are two diameters D Column I Velocity at point I A is 5gl Velocity at point A is less than 2gl Velocity at A is between 2gl and 5gl Velocity at point A is 6 gl II III 0 IV P Column II Tension at point Cis equals to weight of particle Tension at point D is 3mg Tension is non zero everywhere Tension in string is zero some where between B and C P R S Column III Total energy of particle is 3gl Total energy of particle is 3 2 gl Total energy of particle is mgl Total energy of particle is

In atom X a single electron orbits around a stationary nucleus of charge Ze where Z is a constant and e is the magnitude of the electronic charge It requires 47 2 eV to excite the electron from the second Bohr orbit to the third Bohr orbit Take ionization energy of the hydrogen atom 13 6 eV The kinetic energy of electron in ground state of atom X is E eV The value of E is

In measurement of resistance by meter bridge The resistivity of wire increases linearly Then the percentage error is minimum when null point is at Options 1 close to 50 cm 2 close to 57 cm 3 close to 45 cm 4 close to 83 cm

In an experiment with a beam balance an unknown mass m is balanced as shown in fig The value of the unknown mass m is 6cm 8cm A B 12 Kg 6 Kg 8 kg 30 Ka 16Kg E m

Element X in the circuit below has a resistance Rx which depends on the voltage Vx on it for Vx 1 V Rx 12 and for Vx 1 V Rx 2 2 Three such elements are connected with an ideal ammeter as shown below the voltage on the leads of the circuit varies in time as shown in the graph X X X 1 A 1 5 s 2 A 5 s 5 3 A 5 s V V 10 Which of the following combinations of current time is are possible 0 6 A 1 5 s 0 10 20 S

he horizontal part of the U shaped tube shown in the figure is 10 cm and its vertical branches are long enough The cross section of the tube is 1 cm First 20 cm ater is poured into the tube then20 cm oil is poured into the left branch density of water 1000 kg m density of oil 800 kg m The whole system is ccelerated towards the left at an acceleration of a 10 m sec Determine the difference between the level of water and the level of oil in cm a 10m sec 10cm

14 class WholeNumbers 15 public static void main String args 16 this would invoke default constructor NumberSystem N new NumberSystem 17 18 19 20 Default constructor provides the default values to the chiert like a null

The dip angle at point P on earth s surface is 45 If the dip angle is changed by 1 then the change in horizontal component of earth s magnetic field is Options 1 2 3 T 4 R 4 6

In a YDSE experiment the primary sources S which is far away from the slits is moved towards slits symmetrically and slowly As a result S D Screen A Fringe width increases B Fringe width decreases C Positions of corresponding maxima remains same D Intensity of fringes decreases O

The cross section ABC of an optical media of refractive index u 5 3 is as shown in figure The curved surface is given by y x A ray of light travelling parallel to x axis is incident normally on face AB The minimum distance of the incident ray from point A to get refracted ray from surface AC is y cm A 1 cm B 2 9 cm C 4 9 cm D 2 cm ray B J Air x cm

A planet of mass m revolves around sun of mass M along an elliptical orbit such that its minimum and maximum distance from centre of the sun are r and 3r respectively Its time period of revolution will be Options 1 4T 2 2T 3 2r GM GM 2r

A block s suspended from a uniform rope that passes through two ideal pulleys The other enc of the rope is tied to a fixed support as shown in the figure If the pulleys are pulled vertically with forces F 110N and F 90N the F2 system stays at rest Assuming linear mass density of the rope 0 25 kg m and the acceleration of free fall 10 m s find the length in m of the rope Pulleys are not small

For the circuit shown in Figure R 3 22 R 122 C C 2F and L L L 2H The electromotive force of th battery is 1 V Initially the switch is closed and the system is operating in a stationary regime steady state C L R eeeeeee E R The reading of the voltmeter in the stationary regime is

Mohit started to walk straight towards south after walking 10 m he turned to the left and walked 6 m After this he turned to the right and walked 10 m Which direction Mohit is facing now South West North South North East Marks 4 1

Two metallic spheres each of radius R having charges 2Q and Q are joined through a capacitor of capacitance C as shown in the figure Assuming R d the charge on the capacitor long time after the key K is closed is 2Q R Q R K d C

Q1 A capacitor of 50 F capacitance is connected in parallel with a reactor of 22 2 resistance and 0 07 henry inductance across 200 V 50 Hz mains Calculate the total current taken Draw the vector diagram in explanation

A square loop of side a and resistance R is placed with its face in the x y plane A 1 T uniform magnetic field of magnitude Be pointing in 3x 2 direction is applied The magnitude of emt in the loop at time 7 is Options 1 2 1 B a 4 et 1 Ba 2 et where t is time 7 is a constant B a et

Note For this question discrepancy is found in question answer Full Marks is being awarded to all candidates Options 1 An electron accelerated by a potential difference of V possess a de Broglie wavelength A If the accelerating potential is increased by a factor 9 The de Broglie wavelength of electron will be approximately 2 3 0 409 mm 0 137 nm 3 681 nm 4

c Why is it much more difficult to see interference fringes for light reflected from a thick piece of glass than from a thin film Would it be easier if monochromatic light were used 2 a In a bi prism experiment with sodium light 5893 the micrometer reading is 2 32mm When the eye piece is placed at a distance of 100cm from the source If the distance between

The circuit consists of a capacitor inductance and two resistors see figure The voltage across both the resistors is 10 V an the voltage between the points A and B is also 10 V Find the applied voltage U in volts R C O 10 O 20 30 40 A B 0000000 L R

Two mirrors one concave and the other convex are placed at a separation of 40 cm as shown in the figure The principal axis and radii of 40 cm 15 cm 5 P R 20 cm R 20 cm curvature of both the mirrors are the same A point object is placed at a distance of 15 cm from concave mirror Consider 1st reflection by concave then by convex and then again by concave Based on above information answer the following questions The location of image after 1st reflection is

A ball is thrown in the air and follows the displacement function s t t 4t 12 where time t is in seconds and the displacement above the ground in meters Find a The initial height above the ground from which the ball is thrown b At what time does the ball reach its maximum height What is the the maximum height above the ground c Determine when the ball hits the ground

a Number i 1 314E 10 b Number 1 1 314E10 A Units B J Units J please help it s one whole question A and B please thank you Your answer Typed answers are easier for students to read than handwritten notes

In Figure a two concentric coils lying in the same plane carry currents in opposite directions The current in the larger coil 1 is fixed Current i2 in coil 2 can be varied Figur b gives the net magnetic moment of the two coil system as a function of i2 The vertical axis scale is set by Wnets 1 90 x 10 5A m and the horizontal axis scale is set by i25 8 00 mA If the current in coil 2 is then reversed what is the magnitude of the net magnetic moment of the two coil system when i2 6 00 mA Number M O a 2 net 10 5 A m Unet s 0 net s 0 Unit i mA b 195

5 a Light is incident normally on a grating of total ruled width 5 x 10 m with 2500 lines in all Calculate the angular separation of two sodium lines in the first order spectrum Can they be seen distinctly 5 5 Marks b Two light sources are observed one after the other with two Nicole prisms mounted one behind the other as polarizer and analyzer The intensity of beams transmitted by the prisms are observed equal from two sources when the angle between the principal section of the nicols are 45 and 70 respectively Calculate the relative intensities of the two sources

it just touches the ground assume If in an office 10 tubes of 40 W 8 fans of 75W and 2 ACs of 1500W are used for 2 hours a day Calculate the per day in commercial units of energy energy consum

m 9999 band 1 999 A ball is thrown towards a moving train from behind as shown If the coefficient of restitution is e 1 3 the speed with which the ball is thrown so that the ball comes to rest after the collision will be 1 80 m s 3 60 m s 2 20 m s 4 100 m s

A far sighted man can not see objects clearly unless they are at least 36 inches from his eyes What is the approximate focal ength in inches of the lens that will just extend his range of clear vision down to 9 inch Select an answer A B C D 6 inches 16 inches 24 inches 12 inches

2 A disc of radius R having uniform surface density has a concentric hole of radius R R If its mass is M the principal moments of inertia are A M R R M R R M R R 2 4 4 M R R M R R M R R B C D 2 4 M R R M R R M R3 R2 M R3 R2 4 M R R 8 M R3 R2

Which of the following statement s is are correct related to the given circuit diagram as shown in figure 2 A C 302 wwww D www 692 One More Correct Answer s 18 V X www 9 The current flowing through 60 resistor is 3 A The equivalent resistance of the circuit is 6 Q The value of unknown resistor X is 40 The power dissipated is Maximum across unknown resistor O

Figure shows a point object O placed between two parallel Mirrors The distance of object from M is 2 CM and that from M is 4 CM Then M One More Correct Answer s A 8 2 cm C 4 cm M The distance between first two images formed by M is 12 CM The distance between first two images formed by M is 8 CM The distance between first two images formed by My is 8 CM D The distance between first two images formed by M is 4 CM

Resolve the vectors shown in the figure below into components Here the vectors i 1 and j j 6 i 3 tr 1 0 1 0 a k 1 point Find a unit vector u in the opposite direction of the vector v 4 4

4 A satellite of mass m is revolving around the earth in a circular orbit of certain radius At certain point of its orbit the direction of motion of satellite is 3 5 suddenly changed by angle a Given cosa by turning its velocity vector such that speed remains constant The satellite consequently goes to elliptical orbit around earth Find ratio of speed at apogee to speed at perigee 1 3 3 9 2 4 3 02

Po 34 A horizontal cylindrical tube is divided into four parts with the help c two fixed partitions A and B and a movable piston C The tube and th piston C are made from heat insulating materials whereas the fixed partitions A and B are made from a conducting material Volume between the fixed partitions A and B is V and initial volume betweer the fixed partition B and piston C is V These volumes are filled with an ideal mono atomic gas at pressure po and temperature To Outside the piston C pressue is also po Quantity AQ of heat is slowly transferred through the partition A to the gas trapped between the partitions A and B Find temperatures of the gases on both sides of the partition B and heat transferred through it

roblem 2 A particle is moving on top of a 2 dimensional plane with its coordinates given in ian system as x t a sin wt y t a cos wt ss the motion of the particle in terms of polar coordinates p q What is the minimum number of alised coordinates required to describe its motion Draw the trajectory of the particle w if the particle trajectory is changed to the followings repeat the exercise x t 2a sin wt y t a cos 2wt

The figure shows the path of a portion of a light ray as it passes through three different materials Mark out the correct relat among refractive indices of three materials 41 4 t Select an answer A B C H1 H2 H3 H2 1 3 H3 H H3 H2

19 A small metal sphere carrying a charge 0 is located at the centre of a spherical cavity in a large uncharged metallic spherical shell Write the charges on the inner and outer surfaces of the shell Write the expression for the electric field at the point Px Delhi 2014 c Metal Q Air

The distances from the centre of earth where weights of the body are zero and one fourth that of the weight of body on the surface of earth are R radius of earth R 1 0 4 3 R 0 4 3R 2 0 4 4 3R 4 0

A man throws a ball of mass m from a moving plank A The ball has a horizontal component of velocity 3 34 m s 1 U with respect to ground towards another man standing on stationary plank B as shown in the figure The combined mass of plank A with man as well as that of plank B with the other man is 2m each the x y plane represents the horizontal plane which is frictionless If initially plank A was moving with speed ui with respect to ground then the relative velocity of plank B in m s with respect to plank A after the man on plank B catches the ball minus 10 m s is 37 B MARKS X

The Earth s radius is about 6370 km An object that has a mass of 20 kg is taken to a height of above the Earth s surface a What is the object s mass at this height b How much does the object t e how large a gravitational force does it experience at this height Ans a 20 kg b 0 19