Homework Help: Newtons Laws?

1. Sep 28, 2005

ouse

Newtons Laws??????????

well i tied this prpblem
you apply a force of .35 n [up] to a fork and it accelaraion is .15m/s^2 wats its mass in grams
well i tried rearanging the force equation
m=a/f
but i got the worng answer si i thoght i rearanged wrong so i tried swithing the varables but that stil didnt work so i figerd there must be another force the only on i can think of is gravty 9.8 m/s^2 [down] but they are on oppiste sides si i just need to know ehn adding vectors that are both horizantal do u still need to do a vector diagem and get their componants then solve or is there an esier way

2. Sep 28, 2005

hotvette

You are on the right track. There are 2 forces acting in opposite directions. Why do you think you have it wrong?

3. Sep 28, 2005

ISU20CpreE

Hey!!

Try this!! First your error was that you are not converting the force(N), into grams remember that N= kg*m/s^2. So, what you really have is 350g*m/s^2. Then Newton's second law says F=m*a. So, what we do is we divide by the acceleration(a) both sides, as a result you will have m=F/a, the answer should be 2333g.

4. Sep 28, 2005

ouse

It looks like you realize that two forces act on the fork: the applied force of 0.35 N acting upward, and the weight acting downward. Weight depends on mass according to the formula $w = m g$.