An engineer in a locomotive sees a car stuck on a track at a railroad crossing in front of the train. When the engineer first sees the car, the locomotive is 310m from the crossing and its speed is 10m/s. If the engineer's creation time is 0.39s, what should be the magnitude of the minimum deceleration to avoid an accident in m/s2

A woman starts to swim directly across a 8.2-km-wide river. Her speed with respect to the water is 2.3 m/s. The river current carries the woman downstream at a speed of 0.91 m/s. (a)How much time, in seconds, does it take her to cross the river? __s b) How far downstream, in meters, will the river carry her by the time she reaches the other side of the river? __m

A motorcycle starts from rest when t = 0 and travels along a straight road at a constant velocity of 7.0 ft/s² until it reaches a speed of 60 ft/s. Then it maintains this speed. Also, when t = 0, a car located 6000 ft from the motorcycle is traveling toward the motorcycle at a constant speed of 40 ft/s. Determine the time when they intersect.

A hot air balloon is travelling vertically upward at a constant speed of 3.7 m/s. When it is 27 m above ground, a package is released from the ballon. a) After it's released, for how long is the package in the air in units of s? Acceleration of gravity is 9.8 m/s/s.  b)What is the speed just before impact with the ground in m/s?  c) Now assume the hot air balloon is traveling vertically downward at a constant speed of 3.7 m/s. After the package is released, how long is it in the air in s? d) What is the speed just before impact with the ground in m/s?

A train makes a journey in which at a point on its trajectory a speed of 80.0 km / h is measured towards the east, while half an hour later the speed is 65.0 km /h towards the east. Can you calculate the average acceleration in this half hour of travel? a) No, because we do not know the starting position or the final position of that half hour of travel. b) No, because we do not know how the direction of the train changed in the other moments of that half hour of travel. c) Yes, and it has a magnitude of 30.0 km/h?? westward. d) Yes, and it has a magnitude of 30.0 km / h²2? to the east.

Two trains are moving at 30 m/s in opposite directions on the same track. The engineers see simultaneously that they are on a collision course and apply the brakes when they are 1000 m apart. Assuming both trains have the same acceleration, what must this acceleration be if the trains are to stop just short of colliding?

Two trains, each having a speed of 30 km/h, are headed at each other on the same straight track. A bird that can fly 60 km/h flies off the front of one train when they are 60 km apart and heads directly for the other train. On reaching the other train, the (crazy) bird flies directly back to the first train, and so forth.What is the total distance the bird travels before the trains collide?

A race car travels northward on a straight, level track at a constant speed travels 0.745 km in 25.0 s. The return trip over the same track is made in 30.0 s.  What is the average velocity of the car in m/s for the first leg of the run? What is the average velocity for the total trip?

A car travels on a road that is parallel to a train track. The car stops at a traffic light and at the same time a train passes with a constant speed of 12.0 m/s. The car remains stopped for 6.0 s and then leaves with a constant acceleration of 2.0 m/s*. Determine: A) The time it takes the car to reach the train, measured from the moment it stopped at the traffic light. B) The distance that the car traveled from the traffic light until it reached the train. C) The speed of the car at the moment it reaches the train. The solutions should be : A) 22.4 s B) 268.8m C) 32.8m/s