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kobusy [5.1K]
3 years ago
10

A locomotive accelerates a 25-car train along a level track. Every car has a mass of 7.7 ✕ 104 kg and is subject to a friction f

orce f = 250v where the speed v is in meters per second and the force f is in newtons. At the instant when the speed of the train is 29 km/h, the magnitude of the acceleration is 0.20 m/s2.?
Physics
1 answer:
MaRussiya [10]3 years ago
6 0

To solve the problem it is necessary to apply the concepts related to Force of Friction and Tension between the two bodies.

In this way,

The total mass of the cars would be,

m_T = 25(7.7*10^4)Kg

m_T = 1.925*10^6Kg

Therefore the friction force at 29Km / h would be,

f=250v

f= 250*29Km/h

f = 250*29*(\frac{1000m}{1km})(\frac{1h}{3600s})

f = 2013.889N

In this way the tension exerts between first car and locomotive is,

T=m_Ta+f

T=(1.925*10^6)(0.2)+2013.889

T= 3.8701*10^5N

Therefore the tension in the coupling between the car and the locomotive is 3.87*10^5N

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Answer:

Explanation:

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1.3 x 4186 x ( 31.4 - 23 ) =  .45 x s x (91 - 31.4 )

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Explanation:

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From the equation, we see that the field strength decreases as we move away from the sphere: therefore, the strength is maximum for the point closest to the sphere, which is point A.

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