Basic Physics Questions and Answers

4 The shape of moving blades in Reaction turbine is O Concave O Convex Aerofoil Flat 5 Which method is important for maintaining speed of turbine shaft by arranging number of stages in series on shaft O Governing O Compounding O Regenerative feed heating All of the above

1 Which of the following are equivalent to a Joule J Bubble all answers that apply for this question only there could be one answer for this question or there could be more than one answer for this question a N m b kg m s c kg m s d N m s e N m 2 Work done on an object is considered to be zero when a an applied force does not result in any motion of the object b displacement exists in the absence of a force c the applied force is perpendicular to the displacement of the object d a and c are true but b is not true e a b and c are all true

40 A light rod of length pivoted at its lower end on the ground can rotat is any direction A particle of mass m is affixed at its upper end and th rod is held and an angle 0o 37 from the vertical as shown in the figure Now the particle is given a horizontal velocity u 2 m s perpendicula to the rod At an instant in the subsequent motion when the rod exert no force on the particle what is the angle made by the rod with th vertical and what is that horizontal component of velocity of the particl which is perpendicular to the rod Acceleration of free fall is g 10 m s

60 5 moles of SO2 and 5 moles of O are allowed to react At equilibrium it was found that 60 of SO2 is used up If the pressure of the equilibrium mixture is one atmosphere the partial pressure of O is a 0 52 atm c 0 41 atm AT b 0 21 atm d 0 82 atm

3 a A film of refractive index u is illuminated by white light at an angle of incidence i In reflected light two consecutive bright fringes of wavelengths and 2 are found overlapping Obtain an expression for the thickness of the film 4 2 4 Marks

O To reduce speed of blade O Provide path to steam O To increase energy of steam O To remains stable 8 The Sleeve valve mechanism mostly used in O ByPass Governing O Nozzle Control Governing O Throttle Governing O In all of the above Request edit access

The space between two hollow and concentric conducting spheres of radii a and b b a is filled with HO a 3 a material whose dielectric consant varies as k C A exp then find N a distance from the centre of the spheres Calculate the capacity of the system If your answer is N 2 xp b c where A is a constant and r is the

17 In real life applications the transformation of energy from one form to another can be 100 depending on the process of how the energy is converted 18 Wind energy is a renewable energy source 19 Biofuels are considered a non renewable energy source 20 A motor that does 500 J of work in 1 second has the same power as a motor that does 500 J of work in 2 seconds

In the figure a mass m is hung by a light spring TRAY and a light string from the ceiling Both the spring and the string make an angle 0 with the horizontal at equilibrium If the string is suddenly cut then the instantaneous acceleration of the mass m is 10 2g 60 m g 0 g

3 If a book is resting on the palm of your hand and you walk across the hall the work done on the book by your hand is zero because a the force on the book by your hand does not cause the displacement of the book b no forces exist at all on the book i e if you were to draw a FBD of the book no forces would be drawn in the FBD c both a and b are true d the displacement of the book is zero from its initial position to its final position e all of a b and d are true 4 Kinetic energy is being transformed into gravitational potential energy when a a stone is thrown vertically upward b a ball is falling freely downward a car is accelerating downhill d a train is brought to rest by application of the brakes e none of the above

1 A car is moving towards east with a speed of 25 kmh To the driver of the car a bus appears to move towards north with a speed of 25 3 kmh What is the actual velocity of the bus O 50 kmh 30 E of N

Part B True False K 10 marks Please fill in the google form with your correct answer 11 Doing positive or negative work on an object always changes the object s energy 12 Kinetic energy can be defined as stored energy due to the force of gravity 13 When Heat is gained Q is a positive value

14 Ice is one of the few solids that does not float on its liquid due to the shape of its molecule and the forces of attraction between its molecules 15 The Gravitational Potential Energy of an object is always measured with respect to the ground as the reference level 16 Power can be measured in Watts or in Joules per second

09 A conducting rod is rotated about one end in a plane perpendicular to a uniform magnetic field with constant angular velocity The correct graph between the induced emf e across the rod and time t is a c e e4 t t b d H e4

At time t 0 a particle is located at the point 7 1 2 It travels in a straight line to the point 4 2 3 has speed 5 at 7 1 2 and constant acceleration 3i j k Find an equation for the position vector r t of the particle at time t The equation for the position vector r t of the particle at time t is r t i j k Type exact answers using radicals as needed

For a particle in one dimensional box of length L with potential energy V x 0 for L x 0 and V x for x2 Land x 0 an acceptable wave function consistent with the boundary conditions is A B C and D are constants a Acos b B x x c Cx x L d sin D n x

he ES n 2 50 A block of mass M 4 kg is kept on a smooth horizontal plane A bar of mass m 1 kg is kept on it They are connected to a spring as shown the spring is compressed Then what is the maximum compression in the spring for which the bar will not slip on the block when released if coefficient of friction between them is 0 2 spring constant 1000 N m Take g 10 m s2 A 1 cm C 1 25 cm K 1000 N m 16oo o o o o o o oo oood m M Figure 2 159 0 2 B 1 m D 10 cm

Which of the following is are based on the principle of total internal reflection O Mirage O Sparkling of diamonds O Optical fibres All of these

A film of refractive index j is illuminated by white light at an angle of incidence reflected light two consecutive bright fringes of wavelengths 2 and 2 are fo overlapping Show that the thickness of the film is 2 22 1 2 2 2 sin 1

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

2 71 With what minimum acceleration mass Mmust be moved on frictionless surface so that m remains stick to it as shown in figure 2 171 The co efficient of friction between M mis u A ug C umg M m m Figure 2 171 B D umg M

In the system shown thread is inextensible masses of thread and that of pulleys are negligible as compared to the loads to be lifted Friction is absent everywhere If m 1 0 kg m2 2 0 kg and F 20 N then acceleration 2x of pulley A in m s is x Value of is 3 B m A m Answer 00 01 02 03 04 05 06 07 08 09 00 01 02 03 04 05 06 07 8

A ball is projected at an angle 60 with the horizontal with speed 5 2 m s After certain time it makes an angle 45 with the horizontal The speed of the ball at that moment is 468 m

A simple pendulum of mass m and length r is mounted on the flatcar that has constant horizontal acceleration a as shown in figure If the pendulum is released from rest relative to the flatcar at the position 0 0 then the expression of the tension T in the supporting light rod for any value of 0 is A T 3 mg sin 0 2m ao 3m a cose B T 2mg cose 2 m ao 3m a cose C T 2mg cos 0 m ao 2 m a cose D None of these O O o 91

An uncharged capacitor is charged by a battery Work done by battery is E This capacitor is then disconnected from the battery and combined with an identical uncharged capacitor The total energy loss when steady state is reached 3 4 2 12 20 1 3E

A thin uniform rod of mass m and length 1 is hinged at one end making an angle a from the horizontal on the ceiling of a room The other end is supported by a vertical massless string Calculate the angular frequency of small oscillations of this system as shown in Fig 1E 82 20 a AB B Fig 1E 82 O A mg b AT

a ball is thrown vertically upward with a velocity of 144 ft s then its height after t seconds is s 144t 16t a What is the maximum height reached by the ball ft b What is the velocity of the ball when it is 320 ft above the ground on its way up Consider up to be the positive dir ft s What is the velocity of the ball when it is 320 ft above the ground on its way down ft s

These electromagnetic waves are with frequency of giga hertz These are suitable for radar system in aircrafts navigation The radiations are O X rays Gamma rays

ction for questions 9 to 10 square field of side 20m there are onut trees A B at diagonally oppo hers of height 40 m and 20m respectively comes flying over the top of tree A alon ight line towards top of tree B with stant speed of 10 3 m s Same time a bird passes the top of tree A a water je I vertically from the centre of the field wh zes the bird after 1 of firing 2 I the distance of bird from the top of ta when jet was fired

For angles of projection of a projectile at angles 45 0 and 45 0 the horizontal ranges described by the projectile are in the ratio of AIPMT Prelims 2006 1 1 1 3 1 2 2 2 3 ooos ansig y x 4 2 1

ssuming that each atom that decays emits one alpha particle how many alpha particles re emitted per minute by a 0 00147 g sample of 150Gd that is free from its decay roducts The half life of 150Gd is 1 80 106 y and the mass of a 150Gd atom is 149 919 u alpha particles min

Shown below is a horizontal beam that is fixed at the left end and is cyclically operated at the right end by a vertical actuator that deflects it 3 mm up and 10 mm down both from the horizontal position The frequency of cycling is 2 Hz The beam is 250 mm long and has a rectangular cross section of 20 mm width The beam s material is a steel with Sut 440 MPa Syt 370 MPa and a fully modified Se 250 MPa a Using a factor of safety of 1 5 determine the thickness of the beam h for a life of 1 000 hours b Suppose a small hole of 4 mm diameter is drilled at the mid width of the beam at a distance 150 mm from the left end The beam thickness is the same as that determined in Part a Can the beam survive 1 000 cycles of cyclic operation now Justify your answer with calculations 250 mm h K

Which among the following is not a Maxwell s equation of electromagnetism Symbols have their usual meaning d 80 BdA 0 B Ji H 16 2 dhe Hol B dt

37 In the given reaction CH3 CH S CH2 CH Br HOH VOLT X X will be a CH3 CH2 S CH2 CH OH b CH3 c 1 1 mixture of a and b CH2 S CH C d 2 1 mixture of a and b

Please provide Handwritten answer with explanation What situation leads to the emission of light that see from black hole jets O a Photons are colliding with electrons that are moving at relativistic speeds O b Hawking radiation is leaking out from the black hole O c Electrons are jumping from a high energy level down to the ground state of an atom O d Electrons are travelling on curved paths around magnetic field lines at relativistic speeds leading emission of radiation O e Electrons are excited in atoms leading to the emission of coloured light

of two different metals riveted it will the metal with higher coefficient of ansion ards the metal with lower coefficient of expansion 28 E fanar bend at all Twist itself into a helix A steel sphere is to be passed through a circular brass ring At 20 C the outer diameter of sphere is 25 cm and the inner diameter of the ring is 24 9cm If both are heated together at which temperature the sphere would just pass through the ring 20 x 10 C and a 12 10 C 1 125 2 225 C 3 325 C 4 525 C 1 2 3 4 29 g 7 NII C

1 A car moves on a circular path of radius 5 m At one instant the speed of car is 5 m s and it is decreasing at a rate of 5 m s The angle between acceleration vector and velocity vector at this instant is T 1 7 3 RIM E 2 E O 6 3

Problem 9 A nozzle with a radius of 0 21 cm is attached to a garden hose with a radius of 0 95 cm that is pointed straight up The flow rate through hose and nozzle is 0 75 L s a b Calculate the maximum height to which water could be squirted with the hose if it emerges from the nozzle in m Calculate the maximum height in cm to which water could be squirted with the hose if it emerges with the nozzle removed assuming the same flow rate

Suppose swimmer and river both upstream direction the speed of river 5 m sec and the speed of swimmer is 3 m sec in opposite direction and observer is in river obviously at rest so what is net velocity of swimmer with respect to river 10 09 PM

A liquid of density p filled in the vessel as shown is rotated with constant angular velocity about the axis passing through the middle The radius of cylinder is R then 1 The minimum value of o for which the liquid comes out is 2 The value of for which the base of container is just exposed is gH R 3 Volume of liquid remaining in the container in case B is TR H 2 4 Gauge pressure at point A in the container in case B is pgH TE F 3H 4 2gH VR OA

1 A parallel plate capacitor has plates of area 10 cm separated by a distance of 1 mm It is filled with the dielectric mica and connected to a battery of emf 6 volts Find the leakage current through the capacitor 13 Q2 m Resistivity of mica 1 10

42 Two charges 14 C and 4 C are placed at 12 cm 0 0 and 12 cm 0 0 B where B 1 2 x 106 N cm2 and r is in an external electric field E in metres The electrostatic potential energy of the configuration is a 97 9 J 102 1 J c 2 1 J b d 57 2 97 9 J

Two blocks A and B of masses 2m and 3m placed on smooth horizontal surface are connected with a light spring The two blocks are given velocities as shown when spring is at natural length VA 2m A K 0000000000000000 Column l Fig 4E 19 3m B V A minimum magnitude of velocity of A during motion v Amin B maximum magnitude of velocity of A during motion v Amax C maximum magnitude of velocity of B VBmax during motion Column II P Q R D velocity of centre of mass VCM of the S system comprised of blocks A B and poreg ring V SI5 0 7v 5 ANZA

39 Which of the following statements is correct n Magnetic field lines do not form closed loops b Magnetic field lines start from north pole and end at south pole of a magnet 85 e The tangent at a point on a magnetic field line represents the direction of the magnetic field at that point d Two magnetic field lines may intersect each other

Steam is passed through 40 g of ice at 10 C till temperature of mixture becomes 80 C Mass of mixture will be approximately NCERT Pg 289

A handful of soil was mixed in water and left in a jar for some time Different components of soil got segregated and formed layers as shown in the given figure Select the correct option regarding layers X Y and Z ASoil sample having high amount of X than Y and Z is best suited for maize cultivation BSoil sample having almost same amount of Y and Z and comparatively much less amount of X has highest percolation rate and water absorbing capacity CSoil containing more amount of Z and very little X and Y is prominent in areas where Kangaroo rat and Acacia are commonly found DThe space between particles is very large in X however particles are small sized and compactly arranged in Y and Z

Bucket A contains only water an identical bucket B contains water but also contains a solid object in the water Consider the following four situations Which bucket weighs more Column I Column II A The object floats in bucket B and the buckets have the same water level B The object floats in bucket B and the buckets have the same volume of water C The object sinks completely in bucket B and the buckets have the same water level D The object sinks completely in bucket B and the buckets have the same volume of water P Bucket A Q Bucket B R Both buckets have the same weight S The answer cannot be determined from the information given 57

An object of length 30 cm is placed on principal axis of a concave mirror of focal length 30cm Its one end at a distance of 45 cm as shown If length of image is 10x in cm find the value of x 45cm

11 In the figure shown the wavelength and frequency of photons in transition a b and c for hydrogen atoms are A A A and Va Vb and ve respectively then Only One Correct Answer A Vb Va Vc B Vc Va Vb C Vc D X A Aus Review ATA

4 Consider a U shaped smooth wire over which a bead of mass m is thrown with speed V as shown The bead enters semi circular part A and leaves at B What is the magnitude of average force exerted by the bead on the part AB of the wire bead d 2 1 Zero A V d B m 2 mV d wire