Question that i am finding really hard

  • Thread starter Thread starter n_ds
  • Start date Start date
  • Tags Tags
    Hard
AI Thread Summary
The discussion revolves around calculating the maximum acceleration of a 25 kg object being hoisted with a rope that can support a maximum load of 400 N. Participants clarify that the net force acting on the object is determined by subtracting the gravitational force (mg) from the maximum load. The correct formula for net force is established as Fnet = 400 N - mg. The final acceleration is calculated using the formula a = Fnet / m, leading to a solution that participants confirm as correct. The conversation emphasizes understanding the forces acting on the object to solve the problem effectively.
n_ds
Messages
11
Reaction score
0
Hi

I tried this question a couple times, couldn't figure it out, thought maybe you guys could help.

1. The maximum load that can safely be supported by a rope in an overhead hoist is 400N. What is the maximum acceleration that can safely be given to a 25kg object being hoisted vertically upward?

I hope someone can help.

Thanks
 
Physics news on Phys.org
What's the net force on the object if the rope is pulling as hard as it can?

Hint: Identify all forces acting on the object.
 
i can't figure out net force as i do not have acceleration...all i have is what is the max load the rope can take which is 400, the gravity which is -9.8 as it is going upwards and the 25 kg load
 
First find the net force, then use it to find the acceleration.

What forces act on the object? Hint: There are two forces acting. What is the magnitude and direction of each force?
 
I am not sure how to find the net force. Am i right in asuming that the 2 forces acting on the object, is the downward force of m*g and the upwards force of m*-g?
 
n_ds said:
Am i right in asuming that the 2 forces acting on the object, is the downward force of m*g and the upwards force of m*-g?
Gravity acts downward on the object with a force equal to mg. And, no, the upward force does not equal -mg, otherwise the net force would be zero... no acceleration at all.

Besides gravity, what force acts on the object? Hint: Isn't the rope attached to the object?
 
is it 400 N?

so Fnet = 400 - mg?
 
That's it!
 
ok so then this is what i think the solution would be

Fnet = 400 - mg

a= Fnet / m
a= (400 - (25)(9.8))/25

and that should give me the answer i need. That does that seem right to u?
 
  • #10
Perfecto...
 
  • #11
thanks so much for the help i really appreciate it
 
Back
Top