MHB W = F*dAnswer: Work Done by Force F on Cylinder Mass m1: 352.2 J

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The discussion focuses on calculating the work done by a force F on a cylinder resting on a board in a frictionless environment. Given the cylinder's mass of 30 kg, radius of 8 cm, and a pulling force of 44.15 N applied for two seconds, the work done is determined to be 352.2 J. The frictional force is calculated using the coefficient of friction of 0.1, which affects the net forces on both the cylinder and the board. The forum participants discuss the equations needed to analyze the forces and accelerations involved. The conversation emphasizes the importance of understanding the relationship between force, friction, and work in this scenario.
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A cylinder of mass m1 = 30 kg and radius r = 8 cm lies on a board of mass m2 = 60 kg. The ground is frictionless and the coefficient of friction (both static and kinetic) between the board and the cylinder is u = 0.1. The centre of mass of the cylinder is pulled with a force of F = 44.15 for two seconds. Find the work done by force F.
Step 1: I drew a picture

Step 2: determined my knowns which is mass 1= 30 kg, radius = 8 cm, mass 2 = 60, u = 0.1, F= 44.15 for t = 2 sec.

Step 3: T.V.= F

Step 4: Equation: ?
 
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aarce said:
A cylinder of mass m1 = 30 kg and radius r = 8 cm lies on a board of mass m2 = 60 kg. The ground is frictionless and the coefficient of friction (both static and kinetic) between the board and the cylinder is u = 0.1. The centre of mass of the cylinder is pulled with a force of F = 44.15 for two seconds. Find the work done by force F.
Step 1: I drew a picture

Step 2: determined my knowns which is mass 1= 30 kg, radius = 8 cm, mass 2 = 60, u = 0.1, F= 44.15 for t = 2 sec.

Step 3: T.V.= F

Step 4: Equation: ?

Hi aarce! Welcome to MHB! ;)

Let's start with the applicable equations.
The force of friction has a maximum of:
$$F_{f,max} = \mu F_n$$
where $F_n$ is the normal force given by:
$$F_n = m_1 \cdot g$$

The net forces on $m_1$ and $m_2$ are:
$$F_1 = F - F_f$$
$$F_2 = F_f$$

If we assume that the masses start sliding with respect to each other, we have that $F_f = F_{f,max}$.
What will be the respective accelerations then?
 
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