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PHYSICS QUESTIONS AND ANSWERS WITH EXPLANATION

PHYSICS QUESTIONS AND ANSWERS WITH EXPLANATION         This blog post contain multiple choice questions on Velocity, acceleration ,power, efficiency of machine, collision of two bodies etc 1.startinh from rest, a Mercedes-Benz car accelerate uniformly at 45m/s² for 70seconds. What distance does  it cover in thirty-fifth  second of the motion. (A) 1.5x10²km      (B) 1.6 x 10 ⁴km     (C) 1.6 X 10³km  (D) 1.5 x10³km Solution Acceleration ,a =45m/s² Hint : when ever a body accelerate uniformly from rest initial velocity, u=0 The time taken to cover the distance in thirty-fifth second of the motion  is the time interval between   34th – 35th  seconds  Therefore  time t = t₃₅  - t ₃₄ S₃₅=ut +1/2at² S₃₄= ut + ½ at² S = S ₃₅- S₃₄ S=(ut ₃₅+1/2at²₃₅ ) -  (ut ₃₄+ 1/2at²₃₄ ) u=0 S = 1/2 a(t²₃₅ – t²₃₄ ) S=1/2 x 45(35² – 34²) S= 1/2 x45 (1225 – 1156)  S= 1/2  x 45 x69  S = 1552.5 m ...