1. All train cars in this problem are identical and have masses of 45,000 kg each....

1. All train cars in this problem are identical and have masses of 45,000 kg each. Three cars, coupled together, are rolling east at 2.4 m/s. A fourth car, traveling west at 3.4 m/s collides with the three and couples to make a four car unit. A moment later, the train cars contact a car that was at rest on the tracks, and it couples to make a five car train.

a) What is the speed of the five car train?

b) How much (constant) force will be necessary to bring the train to a stop in 250 m? Neglect friction.

Solutions

Expert Solution

This is a question based on collision. In this type of questions, if no external force is present we can apply conservation of linear momentum. And we can apply Newton's second law to get the relationship between force and acceleration. As given in the question force is constant. Thus retardation provided by the force to the train would also be constant.

genius_generous answered 2 years ago

Next > < Previous

Related Solutions

Four identical masses of 2.6 kg each are located at the corners of a square with...

Four identical masses of 2.6 kg each are located at the corners of a square with 1.2 m sides. What is the net force on any one of the masses? ? ?? N toward ...............opposite corner

Four identical masses of mass 700 kg each are placed at the corners of a square...

Four identical masses of mass 700 kg each are placed at the corners of a square whose side lengths are 15.0 cm. Part A) What is the magnitude of the net gravitational force on one of the masses, due to the other three? Part B) What is the direction of the net gravitational force on one of the masses, due to the other three? -toward the center of the square -outward the center of the square

1.Three identical very dense masses of 3500 kg each are placed on the x axis. One...

1.Three identical very dense masses of 3500 kg each are placed on the x axis. One mass is at x1 = -120 cm , one is at the origin, and one is at x2 = 300 cm . What is the magnitude of the net gravitational force Fgrav on the mass at the origin due to the other two masses? Take the gravitational constant to be G = 6.67×10−11 N⋅m2/kg2 . Express your answer in newtons to three significant figures....

Three identical very dense masses of 4300 kg each are placed on the x axis. One...

Three identical very dense masses of 4300 kg each are placed on the x axis. One mass is at x1 = -120 cm , one is at the origin, and one is at x2 = 400 cm . Part A What is the magnitude of the net gravitational force Fgrav on the mass at the origin due to the other two masses? Take the gravitational constant to be G = 6.67×10−11 N⋅m2/kg2 . Express your answer in Newtons.

1. Think about the forces acting on a train engine and the train cars that it...

1. Think about the forces acting on a train engine and the train cars that it pulls. a.) Draw a force diagram for the 5 forces (one of the forces is friction) acting on the engine as it accelerates forward along the rails. b.) Draw a force diagram for the 4 forces acting on a train car as it is pulled by the accelerating engine. c.) By Newton’s 3rd Law, the train car pulls backward on its engine exactly as...

A freight train consists of two 8.1 x 10^4kg engines and 45 cars with average masses...

A freight train consists of two 8.1 x 10^4kg engines and 45 cars with average masses of 5.75 x10^4 kg each. m=8.1x10^4kg m2=5.75x10^4kg f=7.25x10^5 N Part (a): What is the magnitude of the force that each engine must exert backward on the track to accelerate the train at a rate of 5.00x10^-2m/s^2 if the force of friction is 7.6x10^5N, assuming the engines exert identical forces? This is not a large frictional force for such a massive system. Rolling friction for...

A freight train consists of two 8.00 x 105 kg engines and 45 cars with average...

A freight train consists of two 8.00 x 105 kg engines and 45 cars with average masses of 5.50 x 105 kg. (a) Assuming the force of friction is 7.50 x 105 N, calculate the force each engine must exert to accelerate the train at 5.00 x 10-2 m/s2. (b) What is the magnitude of the force in the link coupling the 10th and 11th train cars?

Four point masses each with a mass of 4.90 kg are positioned at the corners of...

Four point masses each with a mass of 4.90 kg are positioned at the corners of a rectangle with dimensions 1.80 meters by 3.00 meters. Assume these are the only masses that are gravitationally relevant. What is the magnitude of the gravitational force on a corner mass due to the other three masses?

A) Three identical very dense masses of 5000kg each are placed on the x axis. One...

A) Three identical very dense masses of 5000kg each are placed on the x axis. One mass is at x1 = -130cm , one is at the origin, and one is at x2 = 400 cm. 1) What is the magnitude of the net gravitational force Fgrav on the mass at the origin due to the other two masses? Take the gravitational constant to be G = 6.67×10−11 N⋅m2/kg2N. Express your answer in newtons to three significant figures. 2) What...

You have two blocks, with respective masses of 8 kg and 12 kg sitting next to...

You have two blocks, with respective masses of 8 kg and 12 kg sitting next to each other on a table. You decide to move them both together, and push on the 8 kg block with a net force of 120 N such that it pushes the 12 kg block along with it. a. Find the acceleration for both blocks. b. Will both blocks feel the same net force? Explain. c. Draw a force diagram on the 8 kg block,...

Subjects