Freight trains can produce only relatively small accelerations. (a) what is the final velocity of a freight train that accelerates at a rate of 0.0500m/s2 for 8.00 min, starting with an initial velocity of 4.00 m/s? (b) if the train can slow down at a rate of 0.550m/s2, how long will it take to come to a stop from this velocity? (c) how far will it travel in each case?

a) 28 m/s   b) 50.9s   c)i)7680m   c)ii) 712m

Explanation:

The acceleration is constant in each case, so lets use the ecuations for this kind of motion.

a) For the velocity we have:

where 480 is the amount of seconds in 8 min

b) In this case we got a 0 velocity, starting with 28 m/s and accelerating at a rate of -0550m/s2 , that means , slowing down.

Solving for t:

c) Now we can use the equation for the position of a particle with constant acceleration.

In the case of a) we have:

In the case of b) we have

Hope my answer helps you.

Have a nice day!

.) the observation by semmelweis that more mothers died of childbed fever when their doctors also worked in the morgue

a.   mass number from atomic number