Solving Mass m2 Acceleration on a 30° Slope

In summary, the conversation discusses a problem involving two masses, m1 and m2, connected by a light string on a 30-degree slope with a frictionless pulley. The question is asking for the scalar equation that shows the relationship between the acceleration of m2 and the tension in the string. The correct answer is FT - m2g sin30^{o} = m2a, which differs from the attempt at a solution presented. The conversation also touches upon the concept of unbalanced forces and their effect on m2.
  • #1
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Homework Statement


A mass, m2, on a 30[tex]^{o}[/tex] slope is connected to another mass, m1, by a light string that passes over a frictionless pulley, as shown. The two masses are equal, the slope is smooth, and the acceleration due to gravity is g.
What is the scalar equation for mass m2, that correctly shows the relationship between the acceleration, a, of the mass and the tension in the string, FT?

http://img220.imageshack.us/img220/4884/inclinexx4.png​

Homework Equations


F = ma
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The Attempt at a Solution


I got sin 30[tex]^{o}[/tex] = [tex]m_{1}[/tex]g - FT/[tex]m_{2}[/tex]a - [tex]m_{2}[/tex]g. However, this is wrong. The answer is supposed to be FT - m2g sin30[tex]^{o}[/tex] = m2a.

Can someone show me where I went wrong please?
 
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  • #2
What two unbalanced forces are on m2?

what is the acceleration of m2 due to the net unbalanced force on m2?
 
  • #3


I would first commend the student for attempting to solve the problem and using relevant equations. However, there seems to be a misunderstanding of the concepts involved. Let me clarify the solution for you.

Firstly, we need to understand that the two masses, m1 and m2, are connected by a light string. This means that the tension in the string, FT, is the same for both masses. This is because the string is not stretched or compressed and therefore has the same force acting on both sides.

Secondly, we need to consider the forces acting on mass m2. These are the weight of m2 (m2g) acting downwards and the tension in the string (FT) acting upwards. The angle between the weight and the slope is 30°, so we can use trigonometry to find the component of m2g acting parallel to the slope, which is m2g sin 30°.

Now, using Newton's second law, we can write the following equation for mass m2:

ΣF = m2a

Where ΣF is the sum of all the forces acting on m2. This can be written as:

FT - m2g sin 30° = m2a

This is the correct scalar equation for mass m2, which shows the relationship between the acceleration, a, and the tension in the string, FT. I hope this helps clarify the solution for you. Remember to always carefully consider the forces acting on an object and use relevant equations to solve problems in physics.
 

Related to Solving Mass m2 Acceleration on a 30° Slope

1. What is the formula for calculating mass m2 acceleration on a 30° slope?

The formula for calculating mass m2 acceleration on a 30° slope is a = g * sin(θ), where a is the acceleration, g is the acceleration due to gravity (9.8 m/s²), and θ is the angle of the slope (30° in this case).

2. How do I determine the acceleration of mass m2 on a 30° slope?

To determine the acceleration of mass m2 on a 30° slope, you will need to know the mass of m2 and the coefficient of friction between m2 and the slope. You can then use the formula a = (m1 * g * sin(θ) - μ * m2 * g * cos(θ)) / (m1 + m2), where a is the acceleration, m1 is the mass of the object at the top of the slope, μ is the coefficient of friction, and θ is the angle of the slope (30°).

3. How does the angle of the slope affect the acceleration of mass m2?

The angle of the slope directly affects the acceleration of mass m2. As the slope becomes steeper (increasing angle), the acceleration of m2 will also increase. This is because the component of gravity pulling m2 down the slope (sin(θ)) will become greater, resulting in a greater acceleration.

4. What is the role of friction in calculating the acceleration of mass m2 on a 30° slope?

Friction plays a significant role in calculating the acceleration of mass m2 on a 30° slope. Friction acts in the opposite direction of motion and reduces the acceleration of m2. The coefficient of friction between m2 and the slope is necessary to determine the force of friction, which is then used in the acceleration formula (a = (m1 * g * sin(θ) - μ * m2 * g * cos(θ)) / (m1 + m2)).

5. How can I use the calculated acceleration to predict the motion of mass m2 on a 30° slope?

Once you have calculated the acceleration of mass m2 on a 30° slope, you can use it to predict the motion of m2. You can use the equation v = u + at, where v is the final velocity, u is the initial velocity (usually 0 m/s), a is the acceleration, and t is the time. You can also use the equation s = ut + 0.5at², where s is the displacement, u is the initial velocity, a is the acceleration, and t is the time. These equations will help you determine the velocity and displacement of m2 on the slope.

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