Calculating the Force Needed to Pull a Block

Join the discussion
Registration is free. Ask a follow-up in this thread, or start your own.
4 replies · 2K views
HodaM
Messages
6
Reaction score
0

Homework Statement


A block with eight of 455 N is being pulled at constant velocity by a force directed at 30 degrees above the horizontal. The friction force on the crate is 1163 N. What is the magnitude of the pulling force?

Homework Equations


Ft= kx
Fnet= ma


The Attempt at a Solution


I tried to use the component method to find the force in the x direction and then so that I could find the pulling force but it doesn't work!
 
Physics news on Phys.org
I tried using 445 N cos 30 degree to find the vector on the x direction, that's how I was taught!
 
445 N is the weight of the block, which acts vertically downwards, so I'm not sure why you're resolving that into the x direction.

You have several pieces of information: the block has a weight of 445N; it is traveling at constant velocity; the pulling force is 30 degrees above the horizontal; the friction acting on the box is 1163N.

So, first things first, I would draw a free body diagram including all the forces. Can you do this?
 
sure, I do

and I did draw it

so to the left is the friction force

and 30 degrees above the horizontal is the acting force

the gravity is 9.81 and from there I can find the mass of the object

and I have to find the pulling force

thank you very much for you help

I will try my best and see what I get