In the 1950s, an experimental train that had a mass of 3.30 104 kg was powered across level track by a jet engine that produced a thrust of 4.90 105 N for a distance of 600 m.

(a) Find the work done on the train.
1 J
(b) Find the change in kinetic energy.
2 J
(c) Find the final kinetic energy of the train if it started from rest.
3 J
(d) Find the final speed of the train if there was no friction.
4 m/s

-how do you find KE?
-whats the "work formula?"
-calculating no friction? isnt that impossible?

1) Work = force • distance

Work = F2•3s = 4.9•105•600 =2.94•10^8 J.

2) work done = energy gained
Kinetic energy gained = 2.94•10^8 J It had 0 Ke to start, so this is its change in KE
3) This is also the final KE of the train
4) KE = m•v²/2
2.94•10^8 = 0.5•3.3•10^4• v²
V = sqrt (2.94•10^8/0.5•3.3•10^4) = 133.5 m/s

hi kylie

you r a exquisitely smart. I'd like to here more about ur brain. Thank you andn see you

girls!!!

Oh, KE is just an abbreviation for "Kung Fu Enthusiasts"! Just kidding, it actually stands for Kinetic Energy. To find the Kinetic Energy, you can use the formula KE = 1/2 * mv^2, where m is the mass of the object and v is the velocity.

Now, the work formula is W = F * d, where W represents work, F is the force applied, and d is the distance covered. It's like the formula for work and it doesn't involve coffee breaks or office drama, although those can be quite tiring too.

As for calculating for no friction, you're right, it's sort of impossible in the real world. But in this problem, it's just a hypothetical scenario to help us find the final speed of the train. So, we can assume there's no friction acting against the train's movement. It's like pretending that gravity doesn't exist when eating a huge slice of cake – it's just for the sake of the calculation.

To find the kinetic energy (KE), you use the formula KE = 1/2 * mass * velocity^2, where mass is the mass of the object and velocity is the object's speed.

The work formula is given by W = F * d * cos(theta), where W is the work done, F is the force applied, d is the displacement, and theta is the angle between the force and the displacement vectors. In this case, theta is 0 because the force and displacement are in the same direction.

In this scenario, calculating the final kinetic energy assuming no friction is an ideal case assuming all the work done on the train is converted into kinetic energy without any losses due to friction or other factors. While this might not be practically achievable, it helps us understand the maximum possible value.

Now let's calculate the answers to the specific questions:

(a) The work done on the train can be calculated using the formula W = F * d. Plugging in the values, we have W = (4.90 * 10^5 N) * (600 m). Evaluating this expression gives us W = 2.94 * 10^8 J.

(b) The change in kinetic energy is equal to the work done on the train. So in this case, the change in kinetic energy is also 2.94 * 10^8 J.

(c) To find the final kinetic energy, we can assume the train starts from rest, which means it initially has zero kinetic energy. So the final kinetic energy is equal to the change in kinetic energy calculated in part (b) i.e., 2.94 * 10^8 J.

(d) If there is no friction, then all the work done on the train is converted into kinetic energy. Using the work-energy principle, we can equate the work done to the change in kinetic energy. So 2.94 * 10^8 J = 1/2 * m * v^2, where m is the mass of the train and v is the final speed. Rearranging the equation, we can solve for v to find the final speed of the train. However, since the mass of the train is not provided in the question, we are unable to calculate the final speed.