4. A train initially at rest, accelerates uniformly until its speed reaches 8 m s-1 in 25 s. For the next 200 s, the train continues its journey with constant speed, before it slows down uniformly and comes to a complete stop in 20 s. (i) Sketch a labelled graph of speed versus time for the whole journey. (ii) Calculate the accelerations of the train for the three parts of the journey. [Answer: a, = 0.32 m s, a, =0 m s², a, =-0.4 m s] (iii) Determine the total distance travelled by the train. [Answer: Distance = 1780 m]

4. A train initially at rest, accelerates uniformly until its speed reaches 8 m s-1 in 25 s. For the next 200 s, the train continues its journey with constant speed, before it slows down uniformly and comes to a complete stop in 20 s. (i) Sketch a labelled graph of speed versus time for the whole journey. (ii) Calculate the accelerations of the train for the three parts of the journey. [Answer: a, = 0.32 m s, a, =0 m s², a, =-0.4 m s] (iii) Determine the total distance travelled by the train. [Answer: Distance = 1780 m]

Name: 4. A train initially at rest, accelerates uniformly until its speed r
Uploaded: 2024-03-05T11:56:34.000Z
Channel: Bartleby
Description: 4. A train initially at rest, accelerates uniformly until its speed reaches 8 m s-1 in 25 s. Forthe next 200 s, the train continues its journey with constant speed, before it slows downuniformly and comes to a complete stop in 20 s.(i) Sketch a labe

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter2: Motion In One Dimension

Section: Chapter Questions

Problem 49P: Traumatic brain injury such as concussion results when the head undergoes a very large acceleration....

See similar textbooks

Similar questions

A motorboat starting from rest travels in a straight line on a lake. (a) If the boat achieves a speed of 8.0 m/s in 10 s, what is the boats average acceleration? (b) Then, in 5.0 more seconds, the boats speed is 12 m/s. What is the boats average acceleration for the total time?
In World War II, there were several reported cases of airmen who jumped from their flaming airplanes with no parachute to escape certain death. Some fell about 20,000 feet (6000 m), and some of them survived, with few life-threatening injuries. For these lucky pilots, the tree branches and snow drifts on the ground allowed their deceleration to be relatively small. If we assume that a pilot's speed upon impact was 123 mph (54 m/s), then what was his deceleration? Assume that the trees and snow stopped him over a distance of 3.0 m.
A person lakes a trip, driving with a constant speed of 89.5 km/h, except, for a 22.0-min rest stop. If the persons average speed is 77.8 km/h, (a) how much time is spent on the trip and (b) how far does the person travel?
Do highway speed limit signs refer to average speeds or to instantaneous speeds? Explain.
A race car moves such that, its position fits the relationship x = (5.0 m/s)t + (0.75 m/s3)t3 where x is measured in meters and t in seconds. (a) Plot a graph of the car's position versus time. (b) Determine the instantaneous velocity of the car at t = 4.0 s, using time intervals of 0.40 s, 0.20 s, and 0.10 s. (c) Compare the average velocity during the first 4.0 s with the results of part (b).
In 1967, New Zealander Burt Munro set the world record for an Indian motorcycle, on the Bonneville Salt Flats in Utah, with a maximum speed of 183.58 mi/h. The one-way course was 5.00 mi long. Acceleration rates are often described by the time it takes to reach 60.0 mi/h from rest. If this time was 4.00 s, and BL11t accelerated at this rate until he reached his maximum speed, how long did it take Burt to complete the course?
A commuter backs her car out of her garage with an acceleration of 1.40 m/s2. (a) How long does it take her to reach a speed of 2.00 m/s? (b) If she then brakes to a stop in 0.800 s, what is her deceleration?
Traumatic brain injury such as concussion results when the head undergoes a very large acceleration. Generally, an acceleration less than 800 m/s2 lasting for any length of time will not cause injury, whereas an acceleration greater than 1 000 m/s2 lasting tor at least 1 ms will cause injury. Suppose; a small child rolls off a bed that is 0.40 m above the floor. If the floor is hardwood, the childs head is brought to rest in approximately 2.0 min. If the floor is carpeted, this stopping distance is increased to about 1.0 cm. Calculate the magnitude and duration of the deceleration. In both cases, to determine the risk of injury. Assume the child remains horizontal during the fall to the floor. Note that a more complicated fall could result in a head velocity greater or less than the speed you calculate.
A car travels on a straight, level road. (a) Starting from rest, the car is going 44 ft/s (30 mi/h) at the end of 5.0 s. What is the cars average acceleration in ft/s2? (b) In 4.0 more seconds, the car is going 88 ft/s (60 mi/h). What is the cars average acceleration for this time period? (c) The car then slows to 66 ft/s (45 mi/h) in 3.0 s. What is the average acceleration for this time period? (d) What is the overall average acceleration for the total time? (Note these convenient British unit conversions: 60 mi/h = 88 ft/s, 45 mi/h = 66 ft/s, and 30 mi/h = 44 ft/s.)
7. If the vehicle velocity changes from 0-60mph in 4.2 s, Calculate the average acceleration whenstarting the motion in (km /hr) 8. If the driver applies the brakes after reaching the maximum speed (189mph), to get a constantacceleration of 4. 5m/s2a. Max. braking distance (Assume constant acceleration)b. Max. Stopping time (Assume constant acceleration)c. If the driver identifies a certain hazard on the way that is 120 m away, will the driver hit theobject or not? Knowing that he was driving with the maximum speed of the car and that thebrakes were applied directly after noticing the obstacle.
3 -The speed of an object moving with constant acceleration increases to 12m/s in 6m/s in 3s. What is the acceleration of the object? A) 6 m/^2 B) 4 m/^2 C) 9 m/^2 D) 1 m/^2 E) 2 m/^2
While driving down a straight road at 70.5 km/h, you pass your physics professor who happens to be out for a jog. He's running at a constant 4.00 m/s, and you decide to slow down and talk physics with him. If you apply your brakes exactly when you pass him on the road, and your car accelerates at 3.58 m/s2 during the breaking, how far do you end up going before he catches up to you?