How long does it take to increase the speed of the train from rest to 78 km/h?

Question

A freight train has a mass of 1.0 107 kg. If the locomotive can exert a constant pull of 7.0 105 N, how long does it take to increase the speed of the train from rest to 78 km/h?

Answer 1

First compute the acceleration using F=m*a
a=7*10^5/(1*10^7)
a=0.07 m/s^2

Next, convert 78 km/hr to m/s
78/3.6=65/3 m/3

now use v=a*t
65/3=0.07*t
t=65/(3*0.07)

5 minutes and 9.5 seconds

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Answer 2

a million. the internet rigidity appearing on the jumper is 9.8 x seventy 8.9 - 88.7; F = m a, so the acceleration would properly be desperate. Plug this into the familiar equation for distance below acceleration, and resolve for t and then v. 2. With uniform deceleration, the undemanding velocity is 14.40 5 m/sec, and it particularly is generally divided into the area to get the time. With this, the deceleration would properly be chanced on, and elevated by ability of the mass to get the rigidity. 3. discern the acceleration utilising F = m a, the place F and m are given. substitute km/hr to m/sec. Divide this by ability of the acceleration to get the time.