What Is the Mass of a Block Pulled with a Force at an Angle?

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A force of 50N acting at 37 degrees pulls a block with constant velocity, and the coefficient of friction is 0.2. The book states the mass of the block is 23.4kg, but some users calculated different values, including 20.3kg and 23.5kg. The discussion highlights the importance of considering the normal force, which is affected by the angle of the applied force. Correctly applying equilibrium equations for both horizontal and vertical components is essential for solving the problem accurately. The confusion arises from the textbook's lack of clarity on how the normal force is influenced by the angle of the pulling force.
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Question: A force of 50N acting at 37degrees above the horizontal pulss a block along the floor with constant velocity. If the coefficient of friction between the blocck and the floor is 0.2, what is the mass of the block?

the answer in the book is 23.4kg

but when I did it I got 20.3kg.

my friend did it and he got 23.4kg but when I use his calcutions and calculated out I get 23.5kg.

He says you have to take the Normal force and substract 50sin37 because its being pulled along that direction. I say do you don't.

Help?
 
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scan said:
the answer in the book is 23.4kg
That is correct.
He says you have to take the Normal force and substract 50sin37 because its being pulled along that direction. I say do you don't.
The fact that the 50N force is applied at angle will definitely affect the normal force. Write down the equilibrium equations for both horizontal and vertical components. Combine the two equations and you can solve for the mass.
 
oh ok. that makes sense now. its just the textbook is so bad that it doesnt' say that the normal force can be affected.
 
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