Okay, so I have an object and they tell me to first find the net force, I know net force means the sum of all forces, they say that the mass of the object is 1.0kg, and it travells ant 5.0m/s and that it enters a region of ice where the coefficient of kinetic friction is 0.10(that part confuses me:confused:) they tell me to find the distance the object travels before coming to a halt. So I drew a diagram with all the forces Fg-gravity Fa-acceleration Ff-friction Fn-natural how do I find the Net Force? What is the natural force(if there is any)

I added the Fa+Ff and got 4.9 do I include Fg and Fn?

Please and thank-you

okay, so i have an object and they tell me to first find the net force, i know net force means the sum of all forces, they say that the mass of the object is 1.0kg, and it travells ant 5.0m/s and that it enters a region of ice where the coefficient of kinetic friction is 0.10(that part confuses me:confused:) they tell me to find the distance the object travels before coming to a halt. so i drew a diagram with all the forces Fg-gravity Fa-acceleration Ff-friction Fn-natural how do i find the Net Force? what is the natural force(if there is any)

i added the Fa+Ff and got 4.9 do i include Fg and Fn?

please and thank-you

Lets try to tackle this one question at a time.

Its good you know the net force is just the sum of all the forces, that's great! It seems though you are confused as to the DIRECTION of these forces.

We know it is traveling at a speed of 5m/s as soon as it enters the platform of ice. The coefficient of friction that is told is what ultimately gives us the information of kenetic friction, which will stop this 1 kg object :D.

On your diagram, you should have F_g pointed down, F_k pointed in the opposite direction of the velocity vector! (This implies the negative acceleration where F_k is the force of friction). And its not the "Natural" force, it is the Normal force, usually this is the force that is opposite of gravity (This is what allows an object like a ball to bounce). F_n should point in the opposite direction of F_g.

Now using F_k=\mu_kF_n to find the decelerating force where \mu_k is the co efficiency of kinetic friction.

Then you can use F_k=ma to figure out what the acceleration is, and use the your kinetics formulas to find out the stopping distance!

When you have finished the above, you should know a,v_o,v_f, just find (x_f-x_o) (This is your displacement or stopping distance).

If you need more help, just post a reply and I'll see what I can do.

Okay, so you say Fn (normal force, my bad) equals -9.8?
And to find the net force I add all the forces together, right?

okay, so you say Fn (normal force, my bad) equals -9.8?
and to find the net force i add all the forces together, right?

Acceleration is not a force ;). If F_g=mg, then F_n=-F_g
So we get F_n=-mg (Note that g is negative, so -g is positive!)

And yes you add F_n+F_g+F_k

Acceleration is not a force ;). If F_g=mg, then F_n=-F_g
So we get F_n=-mg (Note that g is negative, so -g is positive!)

And yes you add F_n+F_g+F_k

oh okay thanks!

oh okay thanks!

Great! Hope you found what you were looking for :cool: