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

  • Thread starter Thread starter scan
  • Start date Start date
  • Tags Tags
    Law Newton's law
AI Thread Summary
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.
scan
Messages
23
Reaction score
0
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?
 
Physics news on Phys.org
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.
 
Thread 'Collision of a bullet on a rod-string system: query'
In this question, I have a question. I am NOT trying to solve it, but it is just a conceptual question. Consider the point on the rod, which connects the string and the rod. My question: just before and after the collision, is ANGULAR momentum CONSERVED about this point? Lets call the point which connects the string and rod as P. Why am I asking this? : it is clear from the scenario that the point of concern, which connects the string and the rod, moves in a circular path due to the string...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top