Question

Лошадь везёт повозку равномерно со скоростью V= 4,5 км в час, прилагая силу модуль которой F= 640 H Какая работа совершается за промежуток времени за промежуток времени 30 минут.

Answer 1

A=F*S 
S=U* t
подставляем 
A=u*t*F
v=4.5 км /час = 4500/3600=1.25 м/c 
t=30мин = 60*30=1800 с 
A=640*1800*1.25=1440 кДж

Answer 2

Calculation of Work Done

To calculate the work done by the horse in pulling the carriage, we can use the formula:

Work = Force x Distance

In this case, the force applied by the horse is given as F = 640 H (H for Horsepower), and the distance traveled is 30 minutes.

However, we need to convert the given force from horsepower to Newtons, as the formula requires force to be in Newtons.

To convert horsepower to Newtons, we can use the conversion factor:

1 horsepower (H) = 745.7 Newtons

Converting the force from horsepower to Newtons:

F = 640 H x 745.7 N/H = 477,248 N

Now, we can calculate the work done by the horse:

Work = Force x Distance

Work = 477,248 N x (30 minutes x 60 seconds/minute)

Note: We need to convert the time from minutes to seconds to match the unit of force.

Calculation

Let's calculate the work done:

Work = 477,248 N x (30 minutes x 60 seconds/minute)

Work = 477,248 N x 1,800 seconds

Work = 859,446,400 N·s

Therefore, the work done by the horse in pulling the carriage over a period of 30 minutes is 859,446,400 N·s.

Please note that the above calculation assumes a constant force and speed throughout the entire duration.