Tiêu đề KINEMATICS.pdf ✅

Kinematics (Motion in a Straight Line & Plane)  Digital www.allendigital.in [ 177 ] DISTANCE & DISPLACEMENT 1. If displacement of a particle is zero, the distance covered : (1) must be zero (2) may or may not be zero (3) cannot be zero (4) depends upon the particle 2. If the distance covered is zero, the displacement : (1) must be zero (2) may or may not be zero (3) cannot be zero (4) depends upon the particle 3. The location of a particle is changed. What can we say about the displacement and distance covered by the particle : (1) Both cannot be zero (2) One of the two may be zero (3) Both must be zero (4) If one is positive, the other is negative and vice-versa 4. The numerical ratio of distance to the displacement covered is always :– (1) less than one (2) equal to one (3) equal to or less than one (4) equal to or greater than one 5. Milkha Singh can cover one round of a circular park in 40 second, After 1 minute and 40 second, he will cover a distance and displacement respectively (R = Radius of circle):- (1) Zero, Zero (2) 4R, R (3) 5R, 2R (4) 6R, 2R 6. A hall has the dimensions 10 m × 10 m × 10 m. A fly starting at one corner ends up at a diagonally opposite corner. The magnitude of its displacement is nearly (1) 5 3 m (2) 10 3 m (3) 20 3 m (4) 30 3 m 7. An ant is scramping on the stairs as shown in the figure. There are '4' stairs and each stair has width of 12 cm and height of 5 cm. The distance travelled by the ant to scramp the stairs is :- (1) 52 cm (2) 68 cm (3) 48 cm (4) 20 cm 8. An insect starts climbing a conical birthday hat of radius 5 cm at base. It starts from point A and reaches point B, taking spiral path on the hat. Find out its displacement if height is 12 cm:- (1) 12 cm (2) 8 cm (3) 13 cm (4) 25 cm 9. Three particles P, Q and R are situated at point A on the circular path of radius 10 m. All three particles move along different paths and reach point B as shown in figure. Then the ratio of distance traversed by particles P and R is : (1) 3 4 (2) 3 1 (3) 3 4  (4) 3  5 12 A B 5 cm 12cm Q O A B R P Exercise - I
NEET : Physics [ 178 ] www.allendigital.in  Digital 10. A body moves along the curved path of a semi circle. Calculate the ratio of distance to displacement: (1) 11 : 7 (2) 7 : 11 (3) 11 : 2  7 (4) 7 : 11 2 11. Distance travelled by the tip of minute hand of length 10 cm in 100 sec is (1) m 180  (2) m 360  (3) m 1200  (4) 3 m 2160  12. If a particle moves from point P(2, 3, 5) to point Q(3, 4, 5). Its displacement vector be :- (1) ˆ ˆ ˆ i j 10k + + (2) ˆ ˆ ˆ i j 5k + + (3) ˆ ˆ i j + (4) 2i 4j 6k ˆ ˆ + + ˆ 13. A man walks 30 m towards north, then 20 m towards east and the last 30 2 m towards south-east. The displacement from origin is : (1) 10 m towards west (2) 50 m towards east (3) 60 2 m towards north west (4) 60 2 m towards east north 14. A person walks 80 m east, then turns right through angle 143° walks further 50 m and stops. His position relative to the starting point is (1) 50 m, 53° east of south (2) 50 m, 53° south of east (3) 30 m, 37° south of east (4) 30 m, 53° south of east 15. A drunkard is walking along a straight road. He takes 5 steps forward and 3 steps backward, followed by 5 steps forward and 3 steps backward and so on. Each step is one meter long and takes one second. There is a pit on the road 13 meters away from the starting point. The drunkard will fall into the pit after : (1) 29 s (2) 21 s (3) 37s (4) 31 s SPEED & VELOCITY, AVERAGE SPEED & AVERAGE VELOCITY 16. A train covers the first half of the distance between two stations with a speed of 30 km/h and the other half with 70 km/h. Then its average speed is : (1) 50 km/h (2) 48 km/h (3) 42 km/h (4) 100 km/h 17. Select the correct statements from the following. S1 :Average velocity is path length divided by time interval. S2. In general, average speed  |average velocity| S3. A particle moving in a given direction with a non-zero velocity can have zero speed. S4. The magnitude of average velocity is the average speed. (1) S1 (2) S2 (3) S3 (4) S4 18. The magnitude of average velocity is equal to the average speed when a particle moves : (1) on a curved path (2) in the same direction (3) with constant acceleration (4) with constant retardation 19. A man walks for some time 't' with velocity (v) due east. Then he walks for same time 't' with velocity (v) due north. The average speed of the man is : (1) 2v (2) 2 v (3) v (4) v 2 20. A car travels a distance d on a straight road in two hours and then returns to the starting point in next three hours. Its average speed and average velocity is : (1) d , 0 5 (2) 2d 5 , 0 (3) 5d d , 6 5 (4) none of these 21. A particle moves in the east direction with 15 m/sec for 2 sec then northwards with 5 m/s for 8 sec. Average velocity of the particle is :– (1) 1 m/s (2) 5 m/s (3) 7 m/s (4) 10 m/s 22. A man walks on an equilateral triangle along path ABC with constant speed then the ratio of average speed and magnitude of average velocity for A to C :-
Kinematics (Motion in a Straight Line & Plane)  Digital www.allendigital.in [ 179 ] (1) 1 (2) 2 (3) 1 2 (4) None 23. A car runs at constant speed on a circular track of radius 10 m taking 6.28s on each lap (i.e. round). The average speed and average velocity for half lap is : (1) Velocity 20/ m/s, speed 10 m/s (2) Velocity zero, speed 10 m/s (3) Velocity zero, speed zero (4) Velocity 10 m/s, speed zero 24. A particle moves in straight line in same direction for 20 sec. with velocity 3 m/s and then moves with velocity 4 m/s for another 20 sec. and finally moves with velocity 5 m/s for next 20 sec. What is the average velocity of the particle? (1) 3 m/s (2) 4 m/s (3) 5 m/s (4) Zero 25. An object travels 10 km at a speed of 100 m/s and another 10 km at 50 m/s. The average speed over the whole distance is :- (1) 75 m/s (2) 55 m/s (3) 66.7 m/s (4) 33.3 m/s 26. A body has speed V, 2V and 3V in first 1/3 part of total travelled distance S, second 1/3 part of S and third 1/3 part of S respectively. Its average speed will be :- (1) V (2) 2V (3) 18 V 11 (4) 11 V 18 27. A body covers one-third of the time with a velocity v1 the second one-third of the time with a velocity v , and the last one-third of the time with a velocity v3. The average velocity is : (1) 1 2 3 vvv 3 + + (2) 1 2 3 1 2 2 3 3 1 3v v v v v v v v v + + (3) 1 2 2 3 3 1 v v v v v v 3 + + (4) 1 2 3 vvv 3 28. If a car cover 2/5th of total distance with v1 speed and 3/5th distance with v2 speed then the average speed is :- (1) 1 2 1 v v 2 (2) 1 2 v v 2 + (3) 1 2 1 2 2v v v v + + (4) 1 2 1 2 5v v 3v 2v + 29. A particle moving in a straight line covers half the distance with speed of 10 m/s. The other half of the distance is covered in two equal time intervals with speed of 4.5 m/s and 7.5 m/s respectively. The average speed of the particle during this motion is : (1) 8.0 m/s (2) 12.0 m/s (3) 10.0 m/s (4) 7.5 m/s 30. A point object traverses half the distance with velocity 0. The remaining part of the distance is covered with velocity 1 for the half time and with velocity 2 for the rest half. The average velocity of the object for the whole journey is (1) 21 (0 + 2) / (0 + 21 + 22) (2) 2 (0 + 1) / (0 + 1 + 2) (3) 20 (1 + 2) / (1 + 2 + 20) (4) 22 (0 + 1) / (1 + 22 + 0) 31. A scooter going due east at 10 ms–1 turns in right side through an angle of 90°. If the speed of the scooter remains unchanged in taking this turn, the change in the velocity of the scooter is :- (1) 20.0 ms–1 in south-west direction (2) Zero (3) 10.0 ms–1 in south-east direction (4) 14.14 ms–1 in south-west direction 32. A person is moving in a circle of radius r with constant speed V. The change in velocity in moving from A to B is (1) 2V cos 40° (2) 2V sin 40° (3) 2V cos 20° (4) 2V sin 20° B A C 40° O A B
NEET : Physics [ 180 ] www.allendigital.in  Digital 33. An insect crawls a distance of 4m along north in 10 s and then a distance of 3m along east in 5 s. The average velocity of the insect is :- (1) 7 m / s 15 (2) 1 m / s 5 (3) 1 m / s 3 (4) 4 m / s 5 ACCELERATION, AVERAGE ACCELERATION & APPLICATION OF CALCULUS 34. The position x of a particle varies with time (t) as x = at2 – bt3. The velocity at time t of the particle will be equal to zero, where t is equal to : (1) 2a 3b (2) a b (3) a 3b (4) a 2b 35. If x denotes displacement in time t and x = a sint, then acceleration is : (1) a cos t (2) – a cos t (3) a sin t (4) –a sin t 36. The motion of a particle is described by the equation x = a + bt2 where a = 15 cm and b = 3 cm/sec2. Its acceleration at time 3 sec will be :- (1) 36 cm/sec2 (2) 18 cm/sec2 (3) 6 cm/sec2 (4) 32 cm/sec2 37. Equation of displacement for a particle is s = 3t3 + 7t2 + 14t + 8 m. Its acceleration at time t = 2 sec is :- (1) 10 m/s2 (2) 16 m/s2 (3) 25 m/s2 (4) 50 m/s2 38. A body is moving according to the equation x = at2 + bt – c. Then its instantaneous speed is given by :– (1) a + 2b + 3ct (2) a + 2bt – 3ct2 (3) 2b – 6ct (4) 2at + b 39. The relation t x 3 = + describes the position of a particle where x is in meters and t is in seconds. The acceleration of particle is :– (1) 2 m/s2 (2) 4 m/s2 (3) 5 m/s2 (4) zero 40. The displacement of a particle is given by y = a + bt + ct3. The initial velocity and acceleration are respectively : (1) b, 0 (2) –b, 2c (3) b, 2c (4) 2c, – 4d 41. Equation of a particle moving along the x axis is x = u(t – 2) + a(t – 2)2 (1) the initial velocity of the particle is u (2) the acceleration of the particle is a (3) the acceleration of the particle is 2a (4) at t = 2 particle is not at origin 42. If for a particle position x  t then :– (1) velocity is constant (2) acceleration is non zero (3) acceleration is variable (4) None of these 43. The velocity of a body depends on time according to the equation = 20 + 0.1t. The body has : (1) uniform acceleration (2) uniform retardation (3) non-uniform acceleration (4) zero acceleration 44. Which of the following relations representing velocity of a particle describes motion with constant acceleration ? (1) v = 6 – 7 t (2) v = 3t2 + 5t3 + 7 (3) v = 9t2 + 8 (4) v = 4t–2 + 3t–1 45. Which of the following equations represents the motion of a body moving with constant finite velocity? in these equations, y denotes the displacement in time t and p, q and r are arbitary constants : (1) y = (p + qt)2 (r + pt) (2) y = p + tqr (3) y = (p + t) (q + t) (r + 1) (4) y = (p + qt)rt 46. The displacement of a particle starting from rest (at t=0) is given by s = 6t2 – t 3 The time when the particle will attain zero acceleration is : (1) 2s (2) 8s (3) 12s (4) 16s 47. The displacement of a particle varies with time according to the relation x = k bt [1 e ] b − − . Then the velocity of the particle is : (1) k(e–bt) (2) 2 bt k b e− (3) kbe–bt (4) None of these