The school zone in front of your school has a posted speed limit of 25 mi/h, which is about 11 m/s. Let’s examine the stopping of a car in several different situations.  a). The crossing guard holds up her stop sign, and the driver is paying attention well. The car moves at a constant velocity of 11 m/s for 2.3 seconds while the driver reacts, then slows down at a constant rate of -4.5 m/s2 . What is the stopping distance for the car in this situation?  b). A child appears to be running into the street ahead. It takes 2.3 seconds for the driver to react and begin to brake, but this time at a rate of -7.5 m/s2 . What is the stopping distance for the car in this situation?   c). The driver is looking at her phone and has a total reaction time of 4.6 seconds as the car is moving at a constant speed of 11 m/s. If the driver slams on her brakes and slows down at a rate of -8.2 m/s2 , what is the stopping distance for the car in this situation?

Part A.) What is the final velocity, in meters per second, of a freight train that accelerates at a rate of 0.095 m/s2 for 8.75 min, starting with an initial velocity of 3.8 m/s?  Part B.) If the train can slow down at a rate of 0.575 m/s2, how long, in seconds, does it take to come to a stop from this velocity?  Part C.) How far, in meters, does the train travel during the process described in part (A)?  Part D.) How far, in meters, does the train travel during the process described in part (B)?

A bird is flying due east. Its distance from a tall building is given by x(t) = 28 m+ (12.4) t-(0.045) ³ t3 a. What is the velocity of the bird when t = 8 seconds? b. What is the acceleration of the bird when t = 8 seconds?

The acceleration of a bus is given by ax(t)=αt, where a = 1.20 m/s3 is a constant. I. If the bus's velocity at time t1 = 1.00 s is 4.90 m/s, what is its velocity of time t2 = 2.15 s? (Express your answer in meters per second.) II. If the bus's position at time t1= 1.00 s is 5.95 m, what is its position at time t2 = 2.15 s? (Express your answer in meters.)

One afternoon, a student was going home after attending a calculus class. For this reason, the student orders an online motorcycle taxi through the application. At the time of ordering, the online motorcycle taxi is in the position s = 2t² + 2t+4, where t is in units of time and s is in meters. a. Determine the average speed of the online motorcycle taxi at intervals of 3 minutes to 5 minutes. b. Determine the time when the instantaneous speed of the online motorcycle taxi is exactly the same as the average speed.    NEED IN RUSH THANKS

You want to figure out just how crazy a driver your friend is. As one of many stop lights begins to change green, you produce a small metal ball on a string and let the ball hang down. As usual, your friend floors the accelerator and you note that while the car is accelerating, the ball sweeps back toward the back of the car so that the ball’s string makes an angle of about 35 degrees with the vertical. What is acceleration of the car in both meters per second squared and in terms of g’s (an acceleration equivalent to what multiple of Earth’s gravitational acceleration g)?

A motorist starts from rest and traveled as seen in the speed-time graph. The total distance traveled and the average velocity in m/s for the distance traveled is 1.5 3.0 4.5 6.0 7.5 Time in minutes Select one: O a. 7.5 km, 4.5 m/s b. 10 km, 1.5 m/s c. 4.5 km, 10 m/s Reply... Speed in km/h :

The position (in meters) of an object is given as a function of time by the equation:                            x(t) = 2t^3 - 3t^2 +t-6                                         a.What is the initial position of the object (that is, at t=0) and What is the position after 3 seconds?   b.What is the average velocity of this object over the first 3 seconds? and   Write an equation for the instantaneous velocity of this object          c.What is the initial velocity of this object (that is, at t=0) and What is the velocity of this object at 3 seconds? Also find the average acceleration for this object over the first three seconds? Please answer it completetely.

3. A jet plane has a takeoff speed of Vtakeoff = 60 m/s and can move along the runway at an average acceleration of 2.0 m/s². The runway is 1.5 km. a. Write out the 3 Kinetic equations. 2. v2-U2= Jas 3.5=uttata2 b. Write out the values of initial position, initial velocity, and acceleration. initial position uloity- a: 0.2m/s init.al aueleradion- How many seconds will it take for the plane to reach takeoff speed? С. d. How far will the plane have to travel to get to takeoff speed? e. will the plane be able to get to 60 m/s before it gets to the end of the runway?

3.) You throw a ball straight up. The ball leaves your hand at a height of 2.00 m above the ground with a speed of 20.0 m/s (~45 mph). Ignore air resistance and use g = 10.0 m/s2 to answer the following questions. You can use a spreadsheet but show your sample calculations. 3a.) Calculate the height, y(t), and velocity, vy(t), at 0.50 second intervals until the ball hits the ground. Show your results in a table and put the units in the column headers: t (s), vy (m/s), y (m). 3b.) Use this data to draw a motion diagram for the ball at 0.50 second intervals. Label the height and the speed at each time interval. Label the origin, starting height, maximum height, and final height. Include the velocity vectors for each time and location of the ball. 3c.) Calculate the time it takes for the ball to hit the ground and the final velocity of the ball just as it hits the ground. Include this velocity vector in your diagram.