A car weighs 1000 kg. It is moving with a uniform velocity of 72 km/h towards a straight road. The driver suddenly presses the brakes. The car stops in 0.2 s. The retarding force applied on the car to stop it is

This question was previously asked in
NDA-II 2024 (GAT) Official Paper (Held On: 01 Sept, 2024)
View all NDA Papers >
  1. 100 N
  2. 1000 N
  3. 10 kN
  4. 100 kN

Answer (Detailed Solution Below)

Option 4 : 100 kN
Free
NDA 01/2025: English Subject Test
5.3 K Users
30 Questions 120 Marks 30 Mins

Detailed Solution

Download Solution PDF

CONCEPT:

Retarding Force (Fretard)

Fretard = m x a

a = (v - u) / t

EXPLANATION:

  • Given data:
    • Mass of the car (m) = 1000 kg
    • Initial velocity (u) = 72 km/h = 72 * (1000/3600) m/s = 20 m/s
    • Final velocity (v) = 0 m/s
    • Time taken to stop (t) = 0.2 s
  • a = (v - u) / t
  • = (0 - 20) / 0.2
  • = -20 / 0.2
  • = -100 m/s2
  • Fretard = m * a
  • = 1000 kg * (-100 m/s2)
  • = -100,000 N
  • The negative sign indicates that the force is in the opposite direction of the motion. The magnitude of the retarding force is:
    • 100,000 N or 100 kN

Therefore, the retarding force applied on the car to stop it is 100 kN.

Latest NDA Updates

Last updated on May 30, 2025

->UPSC has released UPSC NDA 2 Notification on 28th May 2025 announcing the NDA 2 vacancies.

-> A total of 406 vacancies have been announced for NDA 2 Exam 2025.

->The NDA exam date 2025 has been announced for cycle 2. The written examination will be held on 14th September 2025.

-> Earlier, the UPSC NDA 1 Exam Result has been released on the official website.

-> The selection process for the NDA exam includes a Written Exam and SSB Interview.

-> Candidates who get successful selection under UPSC NDA will get a salary range between Rs. 15,600 to Rs. 39,100. 

-> Candidates must go through the NDA previous year question paper. Attempting the NDA mock test is also essential. 

More Motion Questions

Get Free Access Now
Hot Links: teen patti octro 3 patti rummy teen patti real cash teen patti real cash apk