4 3 a b (C) (a 2b) (D) (2a 3b)

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Amelia Leonard
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1 * A balloon is moving verically pwards wih a velociy of 9 m/s. A sone is dropped from i and i reaches he grond in 10 sec. The heigh of he balloon when he sone was dropped is (ake g = 9.8 ms - ) (a) 100 m (b) 00 m (c) 400 m (d) 150 m A balloon is rising verically pwards a a velociy of 10 m/s. When i is a a heigh of 45 m a parachis bails o from i. Afer hree seconds he opens his parache and deceleraes a a consan rae of 5 ms -. Wha was he heigh of he parachis from he grond when he had opened his parache? (g = 10 ms - ) (A) 15 m (B) 30 m (C) 45 m (D) 60 m * From he op of a ower wo sones whose masses are in he raio 1 : are projeced, one sraigh p and he oher sraigh down, boh wih he same speed. Neglecing air resisance, (a) Heavier sone his he grond wih greaer speed (b) Ligher sone his he grond wih greaer speed (c) Boh he sones will have he same speed while hiing he grond (d) The speed canno be deermined wih he given daa * A body is projeced verically pwards. The imes corresponding o heigh h while ascending and while descending are 1 and respecively. The velociy of projecion is (g is acceleraion de o graviy) (a) g 1 (b) g1 1 (c) g 1 (d) g( 1 ) * A body of mass m moving along a sraigh line covers half he disance wih a speed of m/s. The remaining half of he disance is covered in wo eqal inervals of ime wih a speed of 3 m/s and 5 m/s respecively. The average speed of he paricle for he enire jorney in m/s is (a) 8/3 (b) 4/3 (c) 16/3 (d) 3/8 The velociy v of an objec moving in a sraigh line varies wih ime as V = a b where a and b are consans. The average velociy of he objec in he ime inerval = 0 o = sec is 1 (A) a b (B) 4 3 a b (C) (a b) (D) (a 3b) A body is projeced from he grond wih a velociy of a an angle θ wih he horizonal. The average velociy of he body in he ime inerval i akes o reach he highes poin of is rajecory from he poin of projecion is

2 (B) 1 1 cos (C) 1 1 cos (D) 1 1 3cos (A) 1 cos * A moor boa covers a given disance in 6 hr moving downsream in a river. I covers he same disance in 10 hr psream. The ime i akes o cover he same disance in sill waer is (a) 6.5 hr (b) 8 hr (c) 9 hr (d) 7.5 hr (If v is he velociy of boa w.r. waer, v + w is he downsream velociy) * The heigh y and he disance x along he horizonal plane of a projecile on a cerain plane wih no amosphere are given by y 8 5 meer and x 6 meer where is in seconds. The velociy wih which he projecile is projeced in m/s is (a) 6 (b) 8 (c) 10 (d) 14 *The ceiling of a nnel is 5 m high. Wha is he maximm horizonal disance ha a ball hrown wih a velociy of 0 m/s can go wiho hiing he ceiling of he nnel? Take g = 10 ms - (A) 10 3 m (B) 0 3 m (C) 30 3 m (D) 40 m (Only becase he has said maximm horizonal disance do no make range maximm. If yo do so, yo may ge 4 h opion.) Waer drops from a leaky ap are falling a reglar inervals on he grond 15 cm below he ap. The firs drop srikes he grond when he sixh drop js begins o fall. Wha is he heigh of he hird drop from he grond when he firs drop srikes he grond? (g = 10 ms - ) (A) 50 cm (B) 60 cm (C) 70 cm (D) 80 cm * In a lif moving p wih an acceleraion of 5 ms - a ball is dropped from a heigh of 1.5 m. The ime aken by he ball o hi he floor of he lif is nearly (g = 10 ms - ) (a) 0.3 s (b) 0. s (c) 0.16 s (d) 0.4 s A block is placed on op of a smooh inclined plane of inclinaion θ wih he horizonal kep on he floor of a lif. When he lif is descending wih a reardaion a, he block is released. The acceleraion of he block relaive o he incline is (A) g sinθ (B) asinθ (C) (g a) sinθ (D) (g + a) sinθ

3 * A projecile is projeced a 10 m/s a an angle of 60 0 wih he horizonal. Afer some ime is velociy makes an angle of 30 0 wih he horizonal. Is speed a ha insan in m/s is (a) 10 3 (b) 10 3 (c) 5 3 (d) 5 3 * The adjacen figre is a par of horizonally sreched ne. The ension in he par AB is 10 N. Wha are he ensions in BC and BF? (a) 10 N, 11 N (b) 10 N, 6 N (c) 10 N, 10 N (d) can calclae (Yo can answer his js by he argmen of symmery)

4 *Figre shows a block of mass m placed on a horizonal able. The coefficien of saic fricion beween he block and he able is µ. The maximm force F ha can be applied a he poin O sch ha he block does no slip on he srface is (ake he angle made by he sring OA wih he ceiling as θ) (A) mg sin (B) mg cos (C) mg an (D) mg * A shell of mass 0 kg a res explodes ino wo fragmens whose masses are in he raio : 3. The smaller fragmen moves wih a velociy of 6 m/s. The kineic energy of he larger fragmen is (a) 360 J (b) 144 J (c) 16 J (d) 96 J * A mass of 10 kg is sspended by a spring balance. I is plled aside by a horizonal sring so ha i makes an angle of 60 0 wih he verical. The new reading of he balance is (a) 0 kg.w (b) 10 kg.w (c) 10 3 kg.w (d) 0 3 kg.w * A body of mass 0.05 kg is fond o fall wih an acceleraion of 9.5 ms -. The opposing force of air (assmed o be consan) on he body is (g = 9.8 ms - ) (a) 0.15 N (b) 0.03 N (c) zero (d) N * If he linear momen of a body increases by 50 %, hen he kineic energy increases by (a) 5 % (b) 5 % (c) 100 % (d) 15 % de dp (Do no se or else yo will ge opion c.) E p * A block A of mass kg is placed over block B of mass 8 kg. The combinaion is placed over a rogh horizonal srface. Coefficien of fricion beween B and he floor is 0.5 and beween A and B is 0.4. A horizonal force of 10 N is applied on B as shown. The force of fricion beween A and B is

5 (a) 100 N (b) 40 N (c) 50 N (d) zero M = 5 kg and m = 3 kg are placed on he horizonal srface as shown. µ beween he blocks is 0.5 and ha beween M and horizonal srface is 0.7. Wha is he maximm horizonal force F ha can be applied so ha boh move wiho slipping? Take g = 10 ms - Wha do yo hink is he minimm force? How mch is he fricional force beween he blocks in boh cases? Also hink of he siaion wih he force applied on 3 kg body. (A) 4 N (B) 16 N (C) 4 N (D) 96 N * Shell is fired from he cannon wih a speed of 100 m/s a an angle 30 0 wih he verical. A he highes poin of is rajecory, he shell explodes ino wo fragmens of masses in he raio 1:. The ligher fragmen moves verically pwards wih an iniial speed of 00 m/s. wha is he speed in m/s of he heavier fragmen a he ime of explosion? (A) 15 (B) 150 (C) 175 (D) 00 * An aeroplane execes a horizonal loop a a speed of 70 kmph wih is wings banked a Wha is he radis of he loop? Take g = 10 ms - (a) 4 km (b) 4.5 km (c) 7. km (d) km A boy whirls a sone in a horizonal circle m above he grond by means of a sring 1.5 m long. The sring breaks and he sone flies off horizonally, sriking he grond 10 m away. Wha is he magnide of he cenripeal acceleraion in ms - dring circlar moion? Take g = 10 ms -. (A) 100 (B) 00 (C) 300 (D) 400 * The combined mass of a rider and his bike is 00 kg. Wha is he necessary fricional force in N if he has o negoiae a crve 80 m radis a a speed of 7 kmph? Take g = 10 ms - yo can also hink of he angle wih he verical by which he rider has o lean o avoid fricion and falling & sill negoiae he crve. (A) 500 (B) 750 (C) 1000 (D) 150

1. VELOCITY AND ACCELERATION

1. VELOCITY AND ACCELERATION 1.1 Kinemaics Equaions s = u + 1 a and s = v 1 a s = 1 (u + v) v = u + as 1. Displacemen-Time Graph Gradien = speed 1.3 Velociy-Time Graph Gradien = acceleraion Area under