Question

Вагонетка с грузом массой 800 кг начинает двигаться из состояния покоя равноускоренно по прямолинейному горизонтальному пути и через 8с достигает скорости υ=1,6м/с. Определить силу, движущую вагонетку, если сопротивление движению равно 0.01 веса вагонетки.

Answer 1

Відповідь:

Пояснення:Сила равна F=ma, масса на ускорение, ускорение равно a=v/t, скорость на время.

a=1,5/8=1.5 м/с², F=800*1.5=120Н

Answer 2

Problem Analysis

We are given the following information: - The mass of the wagon with cargo is 800 kg. - The wagon starts from rest and reaches a speed of 1.6 m/s in 8 seconds. - The resistance to motion is equal to 0.01 times the weight of the wagon.

We need to determine the force that is moving the wagon.

Solution

To solve this problem, we can use Newton's second law of motion, which states that the net force acting on an object is equal to the product of its mass and acceleration.

The acceleration of the wagon can be calculated using the formula:

acceleration = (final velocity - initial velocity) / time

Substituting the given values, we have:

acceleration = (1.6 m/s - 0 m/s) / 8 s = 0.2 m/s^2

Now, we can calculate the force using the formula:

force = mass * acceleration

Substituting the given mass and calculated acceleration, we have:

force = 800 kg * 0.2 m/s^2 = 160 N

However, we also need to consider the resistance to motion. The resistance force is given as 0.01 times the weight of the wagon. The weight of the wagon can be calculated using the formula:

weight = mass * gravitational acceleration

Substituting the given mass and the acceleration due to gravity (approximately 9.8 m/s^2), we have:

weight = 800 kg * 9.8 m/s^2 = 7840 N

The resistance force is then:

resistance force = 0.01 * weight = 0.01 * 7840 N = 78.4 N

To determine the net force, we subtract the resistance force from the force calculated earlier:

net force = force - resistance force = 160 N - 78.4 N = 81.6 N

Therefore, the force that is moving the wagon is 81.6 N.

Answer

The force that is moving the wagon is 81.6 N.