Question

Автомобиль массой 1т, трогаясь с места, достигает скорости 30 м/с через 20 сек,Найти силу тяги, если коэффициент сопротивления равен 0,05

Answer 1

Дано:
m=1000 кг
v=30 м/с
v0=0
t=20 c
u=0.05
g=10 м/с^2
F-?
Решение:
a=(v-v0)/t=30/20=1.5 (м/с^2)
По 2-ому закону Ньютона: F+Fтр=m*a
При проекциях на ось 0X (сонаправлена с ускорением): F-Fтр=m*a -> F=m*a+Fтр
На ось 0Y (направлена вверх): N-m*g=0 -> N=m*g , где N-сила реакции опоры.
По определению Fтр=u*N=u*m*g -> F=m*a+u*m*g=1000*1.5+0.05*1000*10=
=2000 (Н)
Ответ: 2 кН.

Answer 2

Calculation of Tractive Force

To find the tractive force of a car with a mass of 1 ton (1000 kg) accelerating from rest to a speed of 30 m/s in 20 seconds, we can use the equation:

F = m * a

where F is the tractive force, m is the mass of the car, and a is the acceleration.

Given: - Mass of the car (m) = 1 ton = 1000 kg - Final velocity (v) = 30 m/s - Time taken (t) = 20 seconds - Coefficient of resistance (k) = 0.05

First, we need to calculate the acceleration (a) using the formula:

a = (v - u) / t

where u is the initial velocity (which is 0 m/s since the car is starting from rest).

Substituting the given values:

a = (30 - 0) / 20 = 1.5 m/s^2

Now, we can calculate the tractive force (F) using the formula:

F = m * a

Substituting the given values:

F = 1000 kg * 1.5 m/s^2 = 1500 N

Therefore, the tractive force required for the car to accelerate from rest to a speed of 30 m/s in 20 seconds is 1500 Newtons.

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