3. At a certain moment, a car travelling at 40mph begins braking for a railroad crossing. Assume that the acceleration is constant (and negative!) and that 2 minutes later, the car comes to a stop, just before the crossing. (a) Find a formula for the velocity v(t) at any moment during the deceleration. (Hint: use units in terms of hours, and use (10 in Section 5.4.) (b) Determine how far away from the railroad crossing the car was when it began decelerating. (Hint: (9) in Section 5.4 should help.)

3. At a certain moment, a car travelling at 40mph begins braking for a railroad crossing. Assume that the acceleration is constant (and negative!) and that 2 minutes later, the car comes to a stop, just before the crossing. (a) Find a formula for the velocity v(t) at any moment during the deceleration. (Hint: use units in terms of hours, and use (10 in Section 5.4.) (b) Determine how far away from the railroad crossing the car was when it began decelerating. (Hint: (9) in Section 5.4 should help.)

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

See similar textbooks

Similar questions

1. A train leaves the station on a 50 km commute. The train must make a 60-second stopevery 1.0 km to pick up and drop off passengers. The train accelerates at 2.0 m/s2, then cruises at90 km/h, and then decelerates at 5.0 m/s2 between stops.(a.} How many stops does the train make?(b.} How long does it take for the train to get from one stop to the next?(c.} What is the total time for the entire commute?
You purchase a used car. After handing over the cash, you drive it away from the lot, starting at rest and accelerating at 19.8 m/s2. After 16.9 s, the engine breaks down and it decelerates at 5.9 m/s2 until coming to a stop. How far were you able to drive the car? (Please answer down to the fourth decimal place- i.e 10.3456)
Please solve 13 and 14
1. Two cars, A and B, are travelling in the same direction, although car A is 182 m behind car B. The speed of A is 24.3 m/s, and the speed of B is 18.4 m/s. (a) How much time does it take for A to catch B? (b) If at the end of this time, A begins to decelerate at 2.5 m/s2, calculate the total distance travelled by A.
# 5. An object has the following Velocity-Time graph. If the object had an initial position of x= 8 m at t=0 s, what was the object's final position at t=9 s? (Figure 2.17 might offer a useful reminder) Velocity, v (m/s) 777 Time, t (s) 7
1. A particle moves according to the equation x = 2t³ - 2t + 1, where x is in meters and t in seconds. (a) Find instantaneous acceleration as a function of time. (b) Find the value of the instantaneous acceleration at t = 3.5 s.
1. Jack drives a distance of 160 miles at an average speed of 35 miles/hr, followed by a distance of 190 miles at 75 miles/hr. What is his average speed over the 350-mile trip? Hint: Draw a labeled sketch of the trip. V avg miles per hour
1. A person travels by car from one city to another with different constant speeds between pairs of cities. She drives for 45.0 min at 65.0 km/h, 16.0 min at 70.0 km/h, and 35.0 min at 40.0 km/h and spends 35.0 min eating lunch and buying gas. (a) Determine the average speed for the trip.______km/h(b) Determine the distance between the initial and final cities along the route.______km
A particle moves so that its position (in meters) as a function of time (in seconds) is r = î + 2t² j+ 2tk. (Use the following as necessary: t.) (a) Write an expression for its velocity as a function of time. v(t) = m/s (b) Write an expression for its acceleration as a function of time. d(t) = m/s2 Submit Answer
Please Asap
1. A pilot flies in a straight path for 1 h 30 min. She then makes a course correction, heading 10 degrees to the right of her original course, and flies 2 h in the new direction. If she maintains a constant speed of 610 mi/h, how far is she from her starting position?Your answer is mi;Enter your answer rounded to two decimal places. 2. A steep mountain is inclined 74 degree to the horizontal and rises to a height of 3400 ft above the surrounding plain. A cable car is to be installed running to the top of the mountain from a point 880 ft out in the plain from the base of the mountain. Find the shortest length of cable needed.Your answer is ft
5. Your motion along the x-axis begins at rest and at x= 0. The motion consists of acceleration at 2.00 m/s2for 10.0 s, a time period of 6.00 seconds with no acceleration, and then deceleration at -1.00 m/s2for 20.0 s resulting in a final speed of zero. The total distance traveled is 420 m. What is the average speed during this motion? Give answer to 3 significant figures. Help solve this problem, thanks!