Page 1 :
DEPARTMENT OF PHYSICS, , Physics, Time : 1.00 hr xi Marks : 20, , , , , , , , Description Of Motion In One Dimension, , , , , , 1) A body when released from the top of a tower of height h reaches the ground in time t. At, what time it is at a h height ; above the ground ?, A) B) ; Cc) 3 D) v2T, 2) A person throws ball with velocity v from the top of a building in vertically upward direction, the ball reaches the ground with a speed of 3v then the height of the building is :, a 3v? 67 a?, , A B D}, G MG a 9, , 3) A body is released from a great height and falls freely under gravity vertically towards earth., Another body is released from the same height exactly one second later from the same point., Separation between the two after 2 second of release of the second body is :, , A) 24.5m B) 14.6 m Cc)9.8m D) 4.9m, , 4) Aparachutist after bailing out falls 50 m without friction. When parachute opens, he descends, at 2ms~* and reaches the ground with a speed of 3ms~' . At what height did he bail out ?, A) 111m B) 293 m Cc) 182m D) 91m, , 5) The displacement of a particle is represented by following equation : s = 3t° + 7t? +5t+8, where s is in metre and t in second the acceleration of particle att=1 sis:, A)18ms 2 B) 14ms 2 C)32ms? D) zero, , 6) Acar moving with a speed of 40 km/h can be stopped by applying brakes after at least 2 m. If, the same car is moving with 80 km/h, what is the least stopping distance ?, A)&m B)2m ch4m D)ém, , 7) The displacement x (in meters) of a body varies with time (in sec) as x = ae + 16t +20. The, velocity of body will be zero at time :, , A)8s B) 10s C)16s D) 20s, 8) If a body travels half the distance with velocity v; and next half with velocity vo , its average, velocity will be given by :, Vitve “I 2.1 1, > Cc) > D) oa + =, , 9) The ratio of numerical values of the average velocity and average speed of the body is always, , Av= ire B)y
Page 2 :
A) Unity B) Unity or less C) Unity or more D) Less than unity., 10) If a car at rest accelerates uniformly to a speed of 144 km/h in 20 s, it covers a distance of :, , A) 20m B) 1440 m C) 400 m D) 2980 m, , 11) The position x of a particle varies with time t as x = ut®-bt® . For what value of t acceleration, is zero ?, , 2a a, A) 3b B) a/b Cc) ap D) zero., , 12) A body moves for a total of nine seconds starting from rest with uniform acceleration and, then with uniform retardiation, which is twice the value of accleration and then stops. The, duration of uniform acceleration is :, , A)3s B)45s C)Ss D)6s., , 13) A balloon is rising vertically up with a velocity of 29 ms"! . A stone is dropped from it and it, reaches ground in 10 second. The height of the balloon when the stone was dropped from it, is(g=9.8ms5~*):, , A) 400m B) 150m Cc) 100m D) 200 m, , 14) A particle moves along a straight line OX. At a time t (in second) the distance x (in metre) of, the particle from "O" is given by : x = 40 + 121-19 How long particle travels before coming to, rest ?, , A) 16m B) 21m C) 40m D) 56m, , 15) A body starting from rest moves with constant acceleration "a" . This acceleration is a = pt, where p Is a constant. What is the displacement of particle In a time interval t =0 to t = t, ?, , 1 1 -1 1, A) ge B) apts c) ery D) qty, 16) A small block slides without friction down an inclined plane starting from rest. Let s,, be the, , Sn, , , , , , , , , , , , distance travelled from time t = n-1 tot =n. Then | is:, Sat, 2n-1 2n+1 2n-1 2n, mM 2n 8) 2n-1 c) 2n+1 D) 2n+1, , 17) A parachutist after bailing out falls 50 m without friction. When parachute opens it, decelerates at 2ms * . He lands with a speed of 3ms~' . At what height did he bail out ?, , A) 191m B) 182m C) 293m D) 111m, , 18) A particle located at x = 0 at time t= 0 starts moving along positive x-direction with velocity v, that varies as vy = a\/x . The displacement of the particle varies with time as:, , A)? B)t Cc) v2 pd) &
Page 3 :
19) A car moving with a speed of 50 km/h, can be stopped by brakes after at least 6 m. If the same, car is moving at a speed of 100 km/h, the minimum stopping distance is :, , A) 12m B) 18m C) 24m D)6m, , 20) An automobile travelling with a speed of 60 km/h, can brake to stop within a distance of 20 m., If the car is moving twice as fast i.e. 120 km/h, the stopping distance will be :, , A) 20m B) 80m C) 60m D) 40 m.
