An acceleration

The car goes on a straight road at a speed of 72 km/h. At some point, the driver starts to brake and stops the car in 5 seconds. Find: (a) the acceleration during braking (b) the distance traveled during braking.

Correct answer:

a =  -4 m/s2
s =  50 m

Step-by-step explanation:

v1=72 km/h m/s=72/3.6  m/s=20 m/s v2=0 m/s  t=5 s  a=v2v1t=0205=4 m/s2
s=v1 t+12 a t2=20 5+12 (4) 52=50 m   Verifying Solution:  s0=v1 t=20 5=100 m s0>s



We will be pleased if You send us any improvements to this math problem. Thank you!






avatar




Tips to related online calculators
Do you want to convert length units?
Do you want to convert velocity (speed) units?
Do you want to convert time units like minutes to seconds?

You need to know the following knowledge to solve this word math problem:

Related math problems and questions:

  • Train speed
    train_freight The train speed is decreased during 50 sec from 72 km/h to 36 km/h. Assuming that the train movement is equally slowing, find the the acceleration and the distance that it travels at.
  • Train 2
    zssk_vlak The train slowed down from 90 km/h to 72 km/h in 5 seconds. How long track travel?
  • Driver
    cargo_truck The car driver drives at a speed of 100 km/h, saw the obstacle, and began to brake with a slowing of 5 m/s². What is the length of the pathway to stopping the car when the driver has registered the obstacle with a delay of 0.7 s?
  • Two cities
    cars The car goes from city A to city B at an average speed of 70 km/h, back at an average speed of 50 km/h. If it goes to B and back at an average speed of 60 km/h, the whole ride would take 8 minutes less. What is the distance between cities A and B?
  • Brakes
    pneu The braking efficiency of a passenger car is required to stop at 12.5 m at an initial speed of 40 km/h. What is the acceleration braking by brakes?
  • Car crash
    car1 On the road, with a maximum permitted speed of 60 km/h, there was a car crash. From the length of the vehicle's braking distance, which was 40 m, the police investigated whether the driver did not exceed that speed. What is the conclusion of the police, a
  • Braking distance
    time The car travels at an average speed of 12 km/h and detects an obstacle 10 m in front of it. At 1 m in front of the obstacle it already runs 2 km/h. What is the braking distance? What is the required deceleration for stop in: A) 1m B) 1s?
  • Traffic collision
    crash When investigating a traffic accident, it was found that the driver stopped the vehicle immediately after the accident by constant braking on a 150 m track in 15 seconds. Do you approve that the driver exceeded the permitted speed (50 km/h) in the village
  • Overtaking
    dopravni-znacka-zakaz-predjizdeni On the direct road, the passenger car overtakes the slower bus by starting to overtake 20 meters from the bus and after passing it ahead of it again 20 meters away. The car overtakes at a steady speed of 72 km/h, the bus goes at a steady speed of 54 km/h.
  • Car overtaking
    crash A passenger car travels at a speed of 30 m/s, and before it travels freight truck that drives at a constant speed of 10 m/s. Within 30 meters of the truck, the driver of the car finds out that the truck can not overtake. That's why it starts braking with
  • Car
    sanitka The car drove some distance in 3 hours and 20 minutes. If it increases speed by 10 km/h, it goes this distance in 2.5 hours. Calculate the distance.
  • Forth and back
    forth_and_back Car drive from point A to point B at speed 78 km/h and back at 82 km/h. If went there and back at speed 81 km/h journey would take five minutes less. What is the distance between points A and B?
  • Car driver
    cars The car driver is in town A and is scheduled to be in town B at a specified hour. If it travels at an average speed of 50km/h, it will arrive in city B 30 minutes later. But if he travels at an average speed of 70km/h, he would arrive half an hour earlier
  • Brakes of a car
    motion2 For the brakes of a passenger car to be effective, it is prescribed that a car moving on a horizontal road at a speed of 40 km. A car must stop on the track 15.4 m. What is the deceleration of the car?
  • Truck and car
    smetiari At 6h45min, the truck started at a speed of 36 km/h. At 7h30m behind it a passenger car. Find the passenger car's average speed to catch the truck 72 km away from the factory.
  • Two cars
    car_racing Car A1 goes at average speed of 106 km/h and the second car A2 goes at 103 km/h. How many second will it take car A1 to circulate car A2? Assume that both cars are 5 meters long and the safety gap between cars is 1.5 meters.
  • Cars motion
    AB From point A car start at the speed of 90 km/h. Against it departs from the point B at the same time another car at 60 km/h. For how long and where they met if the distance between A and B is 180 km?