Basic Physics Questions and Answers

e there agnetic agnetic creen S pecific V and ar to a path 4 33 Four long parallel conductors carry equal currents of 5 0A The direction of the currents is into the page at points A and B and out of the page at Cand D Calculate the magnitude and direction of the magnetic field at point P located at the centre of the square AQ BO P 0 2m Figure 4 259 OC 0 2m D

The rectangular plate is deformed into the shape shown by the dashed lines For a 286 and b 413 determine the normal strain along the line of AC 103 sign sensitive unit mm not in scale C 7 b 3 D 60 BI v 10

An elevator is moving upward with unifor acceleration a 4 m s as shown in diagran Determine the tension at mid point of wire AB length 1 m and mass 2 kg A 1 m P 1 50 N 3 80 N 2 kg 2 kg a 4 m s 2 60 N 4 70 N

QED Hack 36 71 Two capacitors of 2 F and 4 F are connected in parallel A third capacitor of 6 F is connected in series The combination is connected across a 12 V battery The voltage across 2 F capacitor is a 2 V c 6 V b 8 V d 1 V Tun identical capacitors are joined in parallel 76

The equivalent resistance of the following infinite network of resistances is 252 ww 4 120 202 ww 202 www 252 ww 252 ww 252 202 www 252 www 292 1 Less than 40 2 40 3 More than 4 Q but less than 12 Q

8 A particle at the end of a spring executes simple harmonic motion with a period t while the corresponding period for another spring is t If the period of oscillation with the two springs in series is T then 2 2 2 T t t 1 T t t 1 1 2 3 T t t 4 T t

A particle is projected from ground with speed 80 m s at an angle 30 with horizontal The magnitude of average velocity of particle in time interval t 2 s to t 6 s is Take g 10 ms A 40 2 m s B 40 m s C Zero D 40 3 m s

Which of the following is are correct regarding vectors A i and B 21 3 A If angle between A and B is 0 then cos 0 B If angle between A and B is 0 then cos 0 C ii is a vector perpendicular to A D i is a vector perpendicular to B 26 1 26

24 Two particles separated at a horizontal dista x as shown in fig they projected at the same as shown in fig with different initial speeds time after which the horizontal distance betw them become zero 1 x 3 30 w c X 2x u 60

A projectile is projected in a plane from origin 44 with intial velocity u u i uj If acceleration due to gravity is taken along j then maximum displacement in x direction would be 1 3 2u u g 4u u g 2 0 500 5 g 45

helicopter with respect to boat in m s A vector makes angle with ve x axis ve y axis respectively 45 60 if the angle made by the vector with ve z axis is 15n What is the value of n Water runs into a conical tank kept with vertex downwards at the rate 9 cm sec If water level is rising at

revolut 15 cm is 25 Air separated from the atmosphere by a column of mercury of length h present in a narrow cylindrical two soldered at one end When the tube is placed horizontally the air occupies a volume V 240 mm When it is set vertically with 3 its open end upwards the volume of the air is V 200 mm The atmospheric pressure V2 3 during the experiment is 7n cm of Hg where

CAREER INSTITUTE Path to SROTA RAJASTHANI 28 In a harbour wind is blowing at the speed of 72 km hr and the flag on the mast of a boat anchored in the harbour flutters along the N E direction If the boat starts moving at a speed of 51 km hr to the north what is the direction of flag on the mast of the boat 28 Nurt GER 42 6917 GIEO V CH NH GI o 2 51 km hr se di oile 42 4 1 42 44

KOTA RAJASTHANT Two blocks each of mass M are resting on a frictionless inclined plane as shown in fig Then 60 B 30 1 the block A moves down the plane 2 the block B moves down the plane 3 both the blocks remain at rest blocks move down the plane 5

Three forces are acting on a body to make resultant force zero Which set can do it without any of the angle between forces being 0 or 180 A 3N 3N 7N B 10N 8N 2N C 3N 3N 6N Use the small angle approximation to find approximate value for sin 1 D 6N 7N 8N

3 A compound microscope has magnifying power of 100 when image is formed at infinity The objective has focal length of 0 5 cm and length of tube is 6 5 cm What is the focal length of eyepiece 1 2 cm 3 3 cm 2 2 5 cm 4 4 cm

Q 2 Assertion A For standard measurement of time Caesium atomic clock is used Reason R The Caesium atomic clocks are very accurate In the caesium atomic clock the second is taken as the time needed for 9 192 631 770 vibrations of the radiation corresponding to the transition between the two hyperfine levels of the ground state of cancis 120

2 In the system shown masses of pulleys and the thread are negligible as compared to masses m 9 0 kg and m 1 0 kg of the blocks The upper pulley is a two step pulley in which radius of the smaller drum is r 1 3 m and that of the larger drum is n 2 times of r At one end the thread is wrapped on the smaller drum of the two step pulley and at the other end the block of mass my is attached There is no friction at the axles of the pulleys whereas friction between the thread and peripheries of the pulleys is sufficient to prevent slipping Acceleration of free fall is g 10 m s When released find acceleration of the block of mass m

A screen is placed 50 cm from single slit which is illuminated with 600 nm light If the distance between first and third minima in diffraction pattern is 3 mm then what is the width of the slit 1 0 2 mm 3 0 5 mm 2 0 3 mm 4 2 3 mm

Two vectors a and 6 of magnitudes 2 units and 4 units respectively are shown in the figure Which of the following mathematical operations is are correct A a b 2 3 b 60 X B a b 4i 2 3 C a b 4 D b 2

B is 1 30 m 2 60 m 3 90 m 4 No 27 Raindrops are falling vertically with a veloci 10m s To a cyclist moving on a straight ro the rain drops appear to be coming with velocity of 20m s The velocity of cyclist is 1 10 m s 2 10 3 m s 4 20 3 m s 6 32 3 20 m s

A a diameter 0 16 m Water is filled in it upto a height of 0 16 m Calculate how long will it take to empty the tank through a hole of radius 5 10 3 m in its bottom 7

Physics book concept of physics is in the shape of a cuboid lxbxh as shown An insect starts moving from O along its length after going half of the length it climbs up the book along the height then it starts moving b along the width by a distance Displacement 3 of insect from initial point is A b h C B b h D None 4 9 2 b h w l

Pat SOTA TRAJASTRIAN 19 Two particles A and B get 4 m closer each 19 AB SOL Ees a esas 0 4 m t second while travelling in opposite direction They get 0 4 m closer every second while travelling in same direction The speeds of A and B are respectively 1 2 2 m sec and 0 4 m sec 2 2 2 m sec and 1 8 m sec 3 4 m sec and 0 4 m sec 4 None of the above 1 2 2 m sec 07 2 2 2 m sec 7 3 4 m sec C 4 449

9 Select the false statement A In elastic collision KE is not conserved during the collision B The coefficient of restitution for a collis between two steel balls lies between 0 and 1 5 25 C The momentum of a ball colliding elastically with the floor is conserved D In an oblique elastic collision between two identical bodies with one of them at rest initially the final velocities are perpendicular

2 Three balls are projected upward with the same initial speed at an angle with horizontal 0 30 45 and 60 respectively Let R be the range of the ball then 1 R0 RR0 30 2 R R 3 R 4 45 R 450 R 30 30 R 60 2 R 20 30 said R 1 RR R 60 2 R600 R450 R 0 R R 60 30 3 R R R 60 450 30 4 R R R 30 60

In the figure the blocks have unequal masses m and m m m m has a downward acceleration a The pulley P has a radius r and some mass The string does not slip on the pulley Find the acceleration of block and angular acceleration of pulley I moment of inertia of pulley olution T T P

The acceleration of a particle is increasing linearly with time t as bt The particle starts from the origin with an initial velocity vo The distance travelled by the particle in time t will be 6 MY P

The plates of an isolated capacitor have equal and opposite charge of magnitude Qo A positive insulator plate having same area as capacitor plates and positive charge Qo is brought just outside the positive plate and kept parallel to it Which of the following options is are correct A The electric field between the capacitor plates increases B The outer surfaces of the capacitor plates have equal and opposite charges C A net attractive force acts on the insulator plate due to the capacitor D The net interaction force between the insulator plate and the negative plate of the capacitor is zero

Three identical bulbs are connected as shown in figure When switch S is open the power consumed in the bulb A is P what is the power consumed by the same bulb when switch S is closed A S m 9P 4P 9 16P 9 B fill ll C

Q No 26 The long straight edges are supported at two points for minimum deflection at centre The distance between supports compared to the length of straight edge should be A 0 5 B 0 554 C 0 577 D 0 6

1 5 h 2 5 2h 4 0 h 3 10 2h A train is moving towards east and a car is along north both with same speed The observed direction of car to the passenger in the train is 1 East north direction 2 West north direction 3 South east direction 4 None of these particle is proiected at 60 to the horizontal

3 24 N 4 240 N 36 The linear momentum P of a body varies with time and is given by the equation P x yt where x and y are constants The net force acting on the body for a one dimensional motion is proportional to 1 1 3 2 a constant

Three immiscible liquids are filled in a container as shown The base area of the container is A and coefficient of cubical expansion of the material of the container is 3 while the coefficient of cubical expansion of the liquids are 2 shown in the figure The temperature of the system is increased by AT The volume of the liquid flown out of the container is A AlyAT 3 B AYAT space for rough work T C L Y 27 3 2ALYAT 3 D AlyAT 2 Pago 1

20 A swimmer crosses the river along the line 20 making an angle of 45 with the direction of flow Velocity of the river is 5 m s swimmer takes 6 seconds to cross river of width 60 m The velocity of the swimmers with respect to water will be 21 2 12 m s 4 10 2 m s 1 10 m s 3 5 5 m s A lead block is suspended from your hand by 232 247 241 62 al well l 1 10 m s 3 5 5m s 21 ssil is oals 42 alle

Am Q 35 2ma 9 a A capacitor of capacitance 0 1F is connected to a battery of emf 8V as shown in the fig Under steady state condition and ii we get A 1052 1002 0 1 F 2002 4A R2013 ww B 1052 BV Option 1 Charge on the capacitor is 0 6 C Solution Option 2 Charge on the capacitor is 0 2 C Option 3 Current in the resistor R between points A B is 0 1 A C Option 4 Current in the resistor R between point A B is 0 4 A Correct Answer Current in the resistor R between point A B is 0 4 A Charging Of Capacitors

In acidic medium MnO4 is converted to Mn 2 when acts as an oxidizing agent The quantity of electricity required to reduce 0 05 mol of MnO4 would be A 0 01F B C skipped 0 05F 0 25 F

3 4 3 31 A man can swim with 10 Km hr in still water He crosses a 1Km wide river through minimum possible distance in 10 minutes The speed of flow of river is 32 1 4 Km hr 3 12 Km hr 2 8 Km hr 4 2 Km hr A body of more 9 kg in hanging from another 3 4 3 km h 31 As a well 10 44 2 1 4 Km hr

pen draws in ink because A its nib is attached to a thin tube that draws th ink in B air pressure inside the tube is increased C some air is filled into the tube D air pressure inside the tube is decreased

A stationary man observes that the rain is falling vertically downward When he starts running with a velocity of 12 km h he observes that the rains is falling at an angle 60 with the vertical The actual velocity of rain is 2 6 3 km h 1 12 3 km h 3 4 3 km h 4 2 3 km h 30 8 see y Euni 439 8 7 43 E 1 12 3 km h

In a system of units if force F acceleration A and time T are taken as fundamental units then the dimensional formula of energy is A FA T C FA T B FAT D FAT

the blocks move down the plane Three blocks are connected as shown in the fig on a horizontal frictionless table If m 1 kg m 8 kg m 27 kg and T3 36 N T T will be T 1 18 3 3 5 3 m T m3 2 9 1 4 4 9 T3 wwwww

B X ray region C Ultra violet region D Microwave region 1474 2 28 In a region density of population is uniform If height of TV tower is doubled then the population which get telecast will be A Double B Triple 12000x10 Tu y Four times D 2 times D 29 Two thin convex lenses of focal length C TRT D Q 28 ffatr 26 FROST A B T C R D 2 1

32 The trajectory of a projectile in a vertical plane is Where a and b are constant and x and y are respectively the horizontal and vertical distances of the projectile from the point of projection The maximum height attained is 1 3 4b y ax bx 2b 4 8b a 2gb 32 Qicia de 9 i a 24471 1 3 4b 2b 33 As a f v pell isa

3 6 m s 4 8 m s An ant is scramping on the stairs as shown the figure There are 4 stairs and each stair b width of 4 cm and height of 2 25 cm T displacement travelled by the ant to scramp stairs is 1 25 cm 3 310 cm An insect sta climbing 2 224 cm 4 337 cm nical birthday

Knowledge Sections Q No 13 IS specifications specify vernier calipers as type A B and C This classification is based on A Accuracy B Least count C Range D Internal or external measurement and for marking purpose

ALLEN CAREER INSTITUTE 40 A person walks up a stalled escalator in 45 sec He is carried in 60s when standing on the same escalator which is now moving The time he would take to walk up the moving escalator will be 1 27 s 2 72 s 40

Ring A can slide on a smooth horizontal rod and block B can move vertically Both are attached by an inextensible string At a certain instant velocity of ring is v and of block is v2 At that instant ring is at a horizontal distance b from pulley as shown Then wwwwwwwww VI 20 B V2 A V VICOSO B a2 a cose where a and a represent the accelerations of block and ring respectively at that instant C V V cos0 D Angular velocity of the ring with respect to an observer on the pulley is v sine a b In a photoelectric effect experiment the frequency of incident radiation is

5 The position of centre of mass of a system o particles does not depend upon which of th following characteristic A forces on particles B position of the particles C masses of particles D relative distance between the particles

A hollow glass sphere of inner radius 5 cm outer radius 10 cm is viewed as shown in figure If refractive index of glass is find distance in cm between A O as seen by the observer Assume near normal incidence of light Air B glass A Air 10cm