Time, Speed and Distance Questions

Multiple choice
  1. 5 km/h

  2. 6 km/h

  3. 6.5 km/h

  4. 7 km/h

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Let Amit's speed be v. Time taken = 30/v. Suresh's time = 30/v - 2. If Amit doubles speed (2v), time = 30/2v = 15/v. This is 1 hour less than Suresh, so 15/v = (30/v - 2) - 1. 15/v = 30/v - 3. 3/v = 15/30? No, 3 = 15/v, so v = 5.

Multiple choice
  1. The displacement of the body is zero.

  2. The average velocity is zero.

  3. The displacement of the body is 30 m.

  4. The average speed of the body is 3m/s.

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

If the particle returns to the starting point, displacement is 0. Average velocity = displacement / time = 0. Average speed = distance / time = 30 / 10 = 3 m/s. Option C claims displacement is 30m, which is false.

Multiple choice
  1. 2 km

  2. 2.5 km

  3. 3 km

  4. 3.5 km

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Anand's total time is 1.25 hours. Let t be the time at 40 km/hr. Distance = 40t + 50(1.25 - t) = 55. 40t + 62.5 - 50t = 55, so 10t = 7.5, t = 0.75 hours. Anand traveled 40 * 0.75 = 30 km before changing speed. Rajesh traveled 30 km at 55/1.5 = 36.67 km/hr. Rajesh's distance = 36.67 * 0.75 = 27.5 km. Difference = 30 - 27.5 = 2.5 km.

Multiple choice
  1. 30 km

  2. 36 km

  3. 45 km

  4. None of these

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Mona's distance is an arithmetic progression: 2, 2.5, 3... The sum of n terms is (n/2)(2*2 + (n-1)*0.5). Rita's distance is 4*n. Total distance is 72 km. Solving (n/2)(4 + 0.5n - 0.5) + 4n = 72 leads to 0.25n^2 + 5.75n - 72 = 0. Multiplying by 4 gives n^2 + 23n - 288 = 0. Factoring gives (n+32)(n-9)=0, so n=9. Rita's distance is 4 * 9 = 36 km.

Multiple choice
  1. 148 km/hr

  2. 128 km/hr

  3. 108 km/hr

  4. 118 km/hr

  5. Data inadequate

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The distance between the stations is constant. Let D be the distance. Speed of train 2 = D/9 = 48 km/hr, so D = 432 km. Speed of train 1 = D/4 = 432/4 = 108 km/hr.

Multiple choice
  1. 75 km

  2. 100 km

  3. 120 km

  4. 150 km

  5. 200 km

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The trains are 100 km apart and move toward each other at 50 km/hr each. Relative speed is 100 km/hr, so they meet in 1 hour. The bird flies at 100 km/hr for that entire hour, covering 100 km.

Multiple choice
  1. 7.5 km

  2. 18 km

  3. 12 km

  4. 20 km

  5. 15 km

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

S travels 15km to B and then some distance back to C. R travels from A to C. Let distance AC = x. S travels 15 + (15 - x) = 30 - x. R travels x. Time is the same: (30-x)/6 = x/4. 120 - 4x = 6x => 10x = 120 => x = 12.

Multiple choice
  1. 8 km

  2. 5 km

  3. 6 km

  4. 7 km

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Let distance be D. Time taken at 5 kmph is D/5, and at 6 kmph is D/6. The difference in time is 12 minutes (6 minutes late + 6 minutes early = 12 minutes = 0.2 hours). D/5 - D/6 = 0.2. Solving gives D/30 = 0.2, so D = 6 km.

Multiple choice
  1. 5:20 pm

  2. 7:20 pm

  3. 5 pm

  4. 7 pm

  5. 9 pm

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Train A starts at 3 PM, speed 30 mph. Train B starts at 3:20 PM, speed 10 mph. By 3:20 PM, Train A has traveled 30 * (20/60) = 10 miles. Remaining distance = 90 - 10 = 80 miles. Relative speed = 30 + 10 = 40 mph. Time to meet = 80 / 40 = 2 hours after 3:20 PM, which is 5:20 PM.