Question

Брусок массой 500 г равномерно перемещают по столу на 40 см. Коэффициент трения между бруском и столом равен 0,3. Чему равна работа силы трения, действующей на брусок?

Answer 1

A=FS=μmgS=0,3*0,5*10*0,4=0,6 Дж

Answer 2

Calculation of the Work Done by Friction

To calculate the work done by the force of friction acting on the block, we need to consider the following information:

- Mass of the block: 500 g - Displacement of the block: 40 cm - Coefficient of friction between the block and the table: 0.3

The work done by a force is given by the formula:

Work = Force × Distance

In this case, the force of friction can be calculated using the formula:

Force of friction = Coefficient of friction × Normal force

The normal force is the force exerted by the table on the block and is equal to the weight of the block, which can be calculated using the formula:

Normal force = Mass × Acceleration due to gravity

Let's calculate the work done by the force of friction step by step:

1. Convert the mass of the block from grams to kilograms: - Mass = 500 g = 0.5 kg

2. Calculate the normal force: - Acceleration due to gravity = 9.8 m/s^2 - Normal force = Mass × Acceleration due to gravity = 0.5 kg × 9.8 m/s^2 = 4.9 N

3. Calculate the force of friction: - Coefficient of friction = 0.3 - Force of friction = Coefficient of friction × Normal force = 0.3 × 4.9 N = 1.47 N

4. Calculate the work done by friction: - Distance = 40 cm = 0.4 m - Work = Force × Distance = 1.47 N × 0.4 m = 0.588 J

Therefore, the work done by the force of friction acting on the block is 0.588 Joules.