Will a block on a table move with a 36N force and what will its acceleration be?

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In summary, the conversation is discussing a block with a weight of 45N on a horizontal table. The block is being pushed by a horizontal force of 36N and has coefficients of static and kinetic friction of 0.65 and 0.42, respectively. The question being asked is whether the block will move under the influence of the force and what its acceleration will be. To solve this problem, one must calculate the resistive force of the coefficients of friction and determine if the applied force is enough to overcome it. Then, if the block does move, the net force on the system can be calculated and used with the mass of the block to determine its acceleration using Newton's second law.
  • #1
explorer
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A block whose weight is 45N rests on a horizontal table.
A horizontal force of 36N is applied to the block .
The coefficients of static and kinetic friction are 0.65 and 0.42, respectively.
Will the block move under the influence of the force, and if so, what will be the block's acceleration?

Thanks for you help.
 
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  • #2
Explorer, this sounds a lot like a homework problem to me. There is a place on the board for this, and I'll request it be moved. To help you with your problem I'll give you some general ideas about this problem.

1st you have the normal force and both coeficients of friction. Look up the equation for how coeffiecients and normal force work together to produce a resistive force.

2nd Calculate what force must be overcome to get the block moving(static friction). Do you have enough force being applying to overcome this barrier?(that's part one)

3rd If the block does slide, calculate the net force on the system( the force of you pushing mius kinetic friction)?

4th use the net force on the system & the known mass of the system with Newtons second law(F=ma) to determine acceleration.

Hope this helps
 
  • #3


Based on the given information, it is possible for the block to move with a 36N force if the force is greater than the maximum static friction force of 29.25N (45N x 0.65). If the applied force is greater than the maximum static friction force, the block will begin to move with an acceleration of 0.8 m/s^2 (36N / 45kg).

Once the block is in motion, the kinetic friction force will come into play and act in the opposite direction of the applied force. The acceleration of the block will then depend on the net force acting on it, which will be the difference between the applied force and the kinetic friction force.

To calculate the kinetic friction force, we can use the formula Fk = μkN, where μk is the coefficient of kinetic friction and N is the normal force (equal to the weight of the block, 45N). This gives us a kinetic friction force of 18.9N (0.42 x 45N).

Therefore, the net force acting on the block will be 17.1N (36N - 18.9N), resulting in an acceleration of 0.38 m/s^2 (17.1N / 45kg).

In summary, the block will move with an acceleration of 0.8 m/s^2 if the applied force is greater than 29.25N, and with an acceleration of 0.38 m/s^2 once it is in motion.
 

1. What is friction?

Friction is a force that occurs when two objects rub against each other, creating resistance and slowing down movement.

2. What causes friction?

Friction is caused by the microscopic roughness of surfaces. When two surfaces come into contact, these tiny bumps and ridges interlock, creating resistance and the force of friction.

3. How does friction affect motion?

Friction can either slow down or stop motion, as it creates a resistance force that opposes the direction of motion. It can also generate heat, which can be useful or detrimental depending on the situation.

4. Can friction be reduced or eliminated?

Friction can be reduced by using lubricants or smoother surfaces, or by reducing the weight or force applied to an object. However, it cannot be completely eliminated as it is a natural force.

5. What are some real-life examples of friction?

Some common examples of friction include walking, where the friction between our feet and the ground allows us to move forward; writing with a pen, where the friction between the pen tip and paper creates the ink trail; and using brakes on a bike or car, where friction helps slow down and stop the vehicle.

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