Question

Перемещаясь равномерно,ученик массой 40 кг поднял на 2-й этаж школьного здания, находящегося на высоте 3 м, груз массой 10 кг. Перемещаясь равномерно, другой ученик массой 45 кг поднял на эту же высоту груз массой 8 кг. Кто из них совершил большую работу?

Answer 1

m1=40кг+10кг

m2=45кг+8кг

 S=3м

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найти А2-А1

 

 

А= F*S

найдём работу первого ученика

 

F1= m*g=(40кг+10кг)*10м/с.кв=500Н

А1= 500Н* 3м=1500Дж

 

найдём работу второго ученика

 

F2= m*g=(45кг+8кг)*10м/с.кв=530Н

А1= 530Н* 3м=1590Дж

1590Дж - 1500Дж = 90Дж

второй ученик совершил рабору больше на 90 Дж

Answer 2

Calculation of Work Done by Each Student

To determine which student performed more work, we need to calculate the work done by each student. Work is defined as the product of force and displacement in the direction of the force. In this case, the force exerted by each student is equal to the weight of the object being lifted, and the displacement is the height to which the object is lifted.

Let's calculate the work done by each student:

1. Student 1: - Mass of the student, m1 = 40 kg - Mass of the object, m1' = 10 kg - Height, h = 3 m

The work done by student 1 is given by the formula: Work1 = Force1 x Displacement1

The force exerted by student 1 is equal to the weight of the object being lifted, which is given by: Force1 = m1' x g, where g is the acceleration due to gravity.

Substituting the values, we have: Force1 = 10 kg x 9.8 m/s^2.

The displacement is the height to which the object is lifted, which is given by: Displacement1 = h.

Therefore, the work done by student 1 is: Work1 = Force1 x Displacement1.

2. Student 2: - Mass of the student, m2 = 45 kg - Mass of the object, m2' = 8 kg - Height, h = 3 m

The work done by student 2 is given by the formula: Work2 = Force2 x Displacement2

The force exerted by student 2 is equal to the weight of the object being lifted, which is given by: Force2 = m2' x g, where g is the acceleration due to gravity.

Substituting the values, we have: Force2 = 8 kg x 9.8 m/s^2.

The displacement is the height to which the object is lifted, which is given by: Displacement2 = h.

Therefore, the work done by student 2 is: Work2 = Force2 x Displacement2.

Calculation Results

Let's calculate the work done by each student:

1. Student 1: - Mass of the student, m1 = 40 kg - Mass of the object, m1' = 10 kg - Height, h = 3 m - Force1 = m1' x g = 10 kg x 9.8 m/s^2 = 98 N - Displacement1 = h = 3 m - Work1 = Force1 x Displacement1 = 98 N x 3 m = 294 J

2. Student 2: - Mass of the student, m2 = 45 kg - Mass of the object, m2' = 8 kg - Height, h = 3 m - Force2 = m2' x g = 8 kg x 9.8 m/s^2 = 78.4 N - Displacement2 = h = 3 m - Work2 = Force2 x Displacement2 = 78.4 N x 3 m = 235.2 J

Comparison of Work Done

Comparing the work done by each student, we find that:

- Student 1 performed 294 J of work. - Student 2 performed 235.2 J of work.

Therefore, Student 1 performed a greater amount of work compared to Student 2.