Question

Автопоезд массой 20 т начал разгоняться из состояния покоя. Определите работу силы тяги автопоезда от начала движения до момента, когда его скорость достигнет значения 10 м/с. Определите модуль ускорения автопоезда, если к этому моменту он проехал 100 м.

Answer 1

A=F*S
F=m*a
S=(v²-v0²)/2*a     v0=0
a=v²/2*S
A=m*(v²/2*S)*S
A=m*v²/2*
A=20*10³*10²/2=10^6Дж

Answer 2

Calculation of Work Done by the Tractive Force

To calculate the work done by the tractive force of the train, we need to determine the distance traveled and the force applied.

Given: - Mass of the train (m) = 20 t = 20,000 kg - Initial velocity (u) = 0 m/s - Final velocity (v) = 10 m/s - Distance traveled (s) = 100 m

The work done (W) can be calculated using the formula:

W = F * s

To find the force (F), we can use Newton's second law of motion:

F = m * a

where: - m is the mass of the train - a is the acceleration of the train

To find the acceleration (a), we can use the equation of motion:

v^2 = u^2 + 2 * a * s

Let's calculate the acceleration first:

a = (v^2 - u^2) / (2 * s)

Substituting the given values:

a = (10^2 - 0^2) / (2 * 100) = 100 / 200 = 0.5 m/s^2

Now, we can calculate the force:

F = m * a = 20,000 kg * 0.5 m/s^2 = 10,000 N

Finally, we can calculate the work done:

W = F * s = 10,000 N * 100 m = 1,000,000 J

Therefore, the work done by the tractive force of the train from the start of motion until it reaches a velocity of 10 m/s is 1,000,000 Joules.

Calculation of the Acceleration of the Train

To calculate the acceleration of the train, we can use the formula:

a = (v^2 - u^2) / (2 * s)

where: - v is the final velocity of the train - u is the initial velocity of the train - s is the distance traveled by the train

Substituting the given values:

a = (10^2 - 0^2) / (2 * 100) = 100 / 200 = 0.5 m/s^2

Therefore, the magnitude of the acceleration of the train at the moment it has traveled 100 meters is 0.5 m/s^2.