Answer:a) 0 b) 47.5mi/h
Explanation:
velocity is vector so you have to consider magnitude and direction
speed is the magnitude of your vector velocity so is just a number not a vector.
time of travel t = 1h+ 45min = 1h + 0.75h = 1.75h
the average speed (constant) is simply v= d/t = ( 2*40 ) /1.75 =45.7mi/h
because we travel 40miles two times so the distance is 80mi.
but the average velocity (two tracks) is clearly zero because here you have to consider the train direction and in both directions the speed is the same but the direction opposite.... so if the speed vectors give sum zero
Answer:
A) 45.17 miles per hour.
B) 0.012 miles per second.
Explanation:
As the distance from Baltimore to Washington DC is about 40 miles, and the train does it twice in 1 hour and 45 minutes, it travels 80 miles in that amount of time.
A) The train travels 80 miles in 1:45 hours, which is equal to 105 minutes. So, as 80/105 is equal to 0.76, it travels 0.76 miles in a minute. As an hour has 60 minutes, its average velocity is of 45.71 miles per hour.
B) An hour has 60 minutes, and each minute has 60 seconds. So, an hour 3,600 has seconds (1 x 60 x 60). As the average speed in hours is of 45.71 mph, we have to divide that number by 3,600 to know the average speed in seconds. So, as 45.71 / 3600 is equal to 0.012, the train's average speed per second is 0.012 miles per second.
