Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
NEETPhysicsMotion in One Dimension

A drone flies parallel to a double railway track. Trains depart from stations at both ends of the track every T minutes, moving at a constant speed of 80 km/h in both directions. The drone meets a train moving in the opposite direction every 12 minutes , and overtakes a train moving in the same direction every 36 minutes . What is the speed of the drone and the time period T of the train service?

Options

  1. A160 km/h , 36 min
  2. B160 km/h , 18 min
  3. C40 km/h , 18 min
  4. D120 km/h , 30 min

Correct answer

A. 160 km/h , 36 min

Step-by-step solution

Let the speed of the drone be v_d and the distance between two consecutive trains be d . Since the trains depart every T minutes at a speed of v_t = 80 km/h , the distance between them is: d = v_t T = 80 T 60 (with T in minutes and d in km) For trains moving in the opposite direction, the relative speed is v_d + 80 . The time interval between encounters is 12 min ( 1 5 h ). d = (v_d + 80) 1 5 For trains moving in the same direction, the drone overtakes them, so the relative speed is v_d - 80 . The time interval is

Practice Motion in One Dimension on Quantrex Academy →

More from Motion in One Dimension

A vehicle runs on a straight road of length 'L'. It travels half the distance with speed V and the remaining distance with speed 3V 2 . Its average speed is 2026For uniform acceleration in linear motion which of the following is NOT CORRECT ? 2026Two cars, P and Q move toward each other, getting 8 m closer every second. If they move in the same direction, they get 0.6 m closer every second. If car P is faster than car Q the 2026A block is kept on the floor of an elevator at rest. The elevator starts descending with acceleration of 5 m/s ^2 . The displacement of the block during the first 0.2 s after the s 2026The acceleration ( a ) -time ( t ) graph for the body starting from rest is as shown in the figure. The maximum speed of the body is 2026A train accelerates from rest at a constant rate 'p' for some time (attains velocity 'v') and then retards to rest at the constant rate 'q'. If the total distance covered by the tr 2026The following plots show variation of velocity ( v ) with time ( t ), of a ball thrown vertically upward, and falling back. Which of the following plots is/are correct ? 2026Consider a particle moving along a straight line, whose position as a function of time is given by s(t)= t^2- t+ , where =1 ms ⁻² , =6 ms ⁻¹ and =5 m. The average speed of the part 2026 Full Motion in One Dimension list All NEET PYQs