04 - LAWS OF MOTION Page 1 ( Answers at the end of all questions )

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1 04 - LAWS OF MOTION Page ) A smooth block is released at rest o a 45 iclie ad the slides a distace d. The time take to slide is times as much to slide o rough iclie tha o a smooth iclie. The coefficiet of frictio is ( a ) µ k = - ( b ) µ k = - µ s = - ( d ) µ s = [ AIEEE 005 ] ) The upper half of a iclied plae with icliatio φ is perfectly smoot w ile the lower half is rough. A body startig from rest at the top will agai come to rest at the bottom if the coefficiet of frictio for the lower half is give by ( a ) cos φ ( b ) si φ ta φ ( d ) ta φ [ AIEEE 005 ] 3 ) A particle of mass 0.3 kg is subjected to a force F = - kx with k = 5 N / m. What will be its iitial acceleratio if it is released from a poit 0 cm away from the origi? ( a ) 5 m /s ( b ) 3 m /s 0 m /s ( d ) 5 m /s [ AIEEE 005 ] 4 ) Cosider a car movig o a straight road with speed of 00 m /s. The distace at which car ca be stopped is [ µ k = 0.5 ] ( a ) 000 m ( b ) 800 m 400 m ( d ) 00 m [ AIEEE 005 ] 5 ) A machie gu fires a bullet of mass 40 g with a velocity of 00 ms -. The ma holdig it ca exert a maximum force o 44 N o the gu. How may bullets ca he fire per secod at the most? ( a ) oe ( b ) four tw ( d ) three [ AIEEE 004 ] 6 ) Two masses m = 5 kg a m = 4.8 kg tied to a strig are hagig over a light frictioless pulley. What is the acceleratio of the masses whe lift is free to move? ( g = 9.8 m / s ) ( a ) 0. m / s ( b 9.8 m / s ( b ) 5 m / s ( d ) 4.8 m / s [ AIEEE 004 ] 7 ) A block rests o a rough iclied plae makig a agle of 30 with the horizotal. The co fficiet of static frictio betwee the block ad the plae is 0.8. If the frictioal force o he block is 0 N, the mass of the block ( i kg ) is ( take g = 0 m / s ) a ).0 ( b ) ( d ).5 [ AIEEE 004 ] 8 ) Three forces start actig simultaeously o a particle movig with velocity v. These forces are represeted i magitude ad directio by the three sides of a triagle ABC as show i the figure. The particle will ow move with velocity ( a ) less tha v ( b ) greater tha v v remaiig uchaged ( d ) l v l i the directio of the largest force BC [ AIEEE 003 ]

2 04 - LAWS OF MOTION Page 9 ) A horizotal force of 0 N is ecessary to just hold a block statioary agaist a wall. The coefficiet of frictio betwee the block ad the wall is 0.. The weight of the block is ( a ) N ( b ) 0 N 50 N ( d ) 00 N [ AIEEE 003 ] 0 ) A marble block of mass kg lyig o ice whe give a velocity o 6 m / s is stopped by frictio i 0 sec. The the coefficiet of frictio is ( Take g = 0 m /s ) ( a ) 0.0 ( b ) ( d ) 0.04 [ NOTE: All these aswers are icorrect. Get correct aswer you self ] [ AIEEE 003 ] ) A body is moved alog a straight lie by a machie del verig a costat power. The distace moved by the body i time t is proportioal o ( a ) t / ( b ) t 3/4 t 3/ ( d ) t /4 [ AIEEE 003 ] ) A sprig balace is attached to the ceilig of a lift. A ma hags his bag o the sprig ad the sprig reads 49 N, whe the lift is statioary. If the lift moves dowwards with a acceleratio of 5 m /s, the readig of the sprig balace will be ( a ) 5 N ( b ) 4 N 49 N ( d ) 74 N [ AIEEE 003 ] 3 ) A rocket with a lift-off mass of kg is blasted upwards with a acceleratio of 0 m /s. The iitial thrust of the blast is ( take g = 0 m /s ) ( a ) N ( b ) N N ( d ) N [ AIEEE 003 ] 4 ) A block of mass M is pulled alog a horizotal frictioless surface by a rope of mass m. If a force P is applie at the free ed of the rope, the force exerted by the rope o the block is Pm Pm PM ( a ) P ( b ) ( d ) [ AIEEE 003 ] + m M - m M + m 5 ) A box is yig o a iclied plae. If the box starts slidig whe the agle of icliatio is 60, the the coefficiet of static frictio of the box ad the plae is ( a ).73 ( b ) ( d ) 0.76 [ AIEEE 00 ] 6 ) If he force o a rocket movig with a velocity of 300 m / s is 0 N, the the rate of fue combustio is ( a ) 0.7 kg / s ( b ).4 kg / s.8 kg / s ( d ) 0.7 kg / s [ AIEEE 00 ] ) A force F is applied o the square block of edge legth a so that the block remais statioary o the vertical wall. The the icorrect statemet is ( a ) f = mg, where f is the frictioal force ( b ) F = N where N is the ormal reactio from the wall F does ot produce ay torque ( d ) N does ot produce ay torque [ IIT 005 ]

3 04 - LAWS OF MOTION Page 3 8 ) A small block slides without frictio dow a iclied plae startig from rest. Let s s be the distace traveled from time t = - to t =. The is s ( a ) ( b ) ( d ) [ IIT 004 ] ) What is the maximum value of the force F such that the block show i the arragemet, does ot move? ( a ) 0 N ( b ) 0 N N ( d ) 5 N [ IIT 003 ] 0 ) A small block is shot ito each of the four tracks s show below. Each of the track rises through the same height. The speed with which he block eters the track is the same i all cases. At the highest poit of the track, the ormal reactio is maximum i: [ IIT 00 ] ) A strig of egligible mass goig over a clamped pulley of mass m supports block of mass M as show i the figure. The force o th pu ley by the clamp is give by: ( a ) Mg ( b ) mg (M + m) + m g ( d ) (M + m) + M g [ IIT 00 ] ) The pulleys ad strigs show i the figure are smooth ad of egligible mass. For the system to remai i equilibrium, the agle θ should be ( a ) 0 ( b ) ( d ) 60 [ IIT 00 ] 3 ) A isect crawls up a hemispherical surface very slowly ( see the figure). The coefficiet of frictio betwee the surface ad the isect is /3. If the lie joiig the cetre of the hemispherical surface to the isect makes a agle α with the vertical, the maximum possible value of α is give by ( a ) cot α = 3 ( b ) ta α = 3 sec α = 3 ( d ) cosec α = 3 [ IIT 00 ]

4 04 - LAWS OF MOTION Page 4 4 ) A cubical block of side L rests o a rough horizotal surface with coefficiet of frictio µ. A horizotal force F is applied o the block as show. If the coefficiet of frictio is sufficietly high so that the block does ot slide before topplig, the miimum force required to topple the block is mg mg ( a ) ifiitesimal ( b ) ( d ) mg ( - µ ) 4 [ IIT 000 ] 5 ) A closed compartmet cotaiig gas is movig with some acceleratio i horizotal directio. Neglect effect of gravity. The the pressure i the compartmet is ( a ) same everywhere ( b ) lower i frot side lower i rear side ( d ) lower i upper side [ IIT 999 ] 6 ) A block of mass 0. kg is held agaist a wall by pp ig a horizotal force of 5 N o the block. If the coefficiet of frictio betwee the block ad the wall is 0.5, the magitude of the frictioal force actig o the block is ( a ).5 N ( b ) 0.98 N 4.9 N ( d ) 0.49 N [ IIT 994 ] 7 ) A particle P is slidig dow a frictioless hemispherical bowl. It passes the poit A at t = 0 At his istat of time, the horizotal compoet of its ve ocity is v. Frictio betwee the bead ad the strig may be eglected. Let t p ad t q be the respective times ake by P ad Q to reach the poit B. The tp legth of arc ACB ( a ) t p < t q ( b ) t p = t q ( c t p > t q (d) = [ IIT 993 ] tq legth of chord AB 8 ) A car is movig i a ci cular horizotal track of radius 0 m with a costat speed of 0 m / s. A plumb bob is suspeded from the roof of the car by a light rigid rod of legth.00 m. The agle made by the rod with the track is ( a ) zero ( b ) ( d ) 60 [ IIT 99 ] 9 ) Whe a bicy le is i motio, the force of frictio exerted by the groud o the two whe ls is such that it acts ( a ) the backward directio o the frot wheel ad i the forward directio o the r ar wheel ( b ) i the forward directio o the frot wheel ad i the backward directio o the rear wheel i the backward directio o both the frot ad the rear wheels ( d ) i the forward directio o both the frot ad the rear wheels [ IIT 990 ] 30 ) A referece frame attached to the earth: ( a ) is a iertial frame by defiitio ( b ) caot be a iertial frame because the earth is revolvig roud the su is a iertial frame because Newto s laws are applicable i this frame ( d ) caot be a iertial frame because the earth is rotatig about its ow axis [ IIT 986 ]

5 04 - LAWS OF MOTION Page 5 3 ) The sprig balace A reads kg with a block m suspeded from it. A balace B reads 5 kg whe a beaker with liquid is put o the pa of the balace. The two balaces are ow so arraged that the hagig mass is iside the liquid i the beaker as show i the figure. I this situatio ( a ) the balace A will read more tha kg ( b ) the balace B will read more tha 5 kg the balace A will read less tha kg ad B will read more tha 5 kg ( d ) the balace A ad B will read kg ad 5 kg respectively [ IIT 985 ] 3 ) I the arragemet show i the figure,the eds P ad Q of a ustretchable strig move dowwards with uiform sp ed U. Pulleys A ad B are fixed. Mass M moves upwar s with a speed ( a ) U cos θ ( b ) U /cos θ U / cos θ ( d ) U cos θ [ IIT 98 ] 33 ) A vessel cotaiig water is give a costat acceleratio a towards the right, alog a straight horizotal path. Which of the diagrams represets the surf ce of the liquid? [ IIT 98 ] 34 ) A ship of mass 3 x 0 7 kg, iitially at rest, is pulled by a force of 5 x 0 4 N through a distace of 3 m Assumig that the resistace due to water is egligible, the speed of the ship is ( a ).5 m / s ( b ) 60 m / s 0. m / s ( d ) 5 m / s [ IIT 980 ] 35 ) A block of mass kg rests o a rough iclied plae makig a agle of 30 with the h izotal. The coefficiet of static frictio betwee he block ad the plae is 0.7. The frictioal force o the block is ( a ) 9.8 N ( b ) 0.7 x 9.8 x 3 N 9.8 x 3 N ( d ) 0.7 x 9.8 N [ IIT 980 ] Aswers b d c a d a a c a # c b c d b a d c a a d c a c b b a c a,c b,d b,c b c c d # All aswers are icorrect. The correct aswer is 0.06.

NARAYANA I I T / N E E T A C A D E M Y. CPT 4 XII-P LJ JEE-ADVANCE-2016-P2-Model

NARAYANA I I T / N E E T A C A D E M Y CPT XII-P LJ JEE-ADVANCE-06-P-Model Time: 3 hr. IMPORTANT INSTRUCTIONS Max Marks: 86 PHYSICS: Sectio Questio Type +Ve - Ve No.of Total Marks Marks Qs marks Sec I(Q.N