# Homework Help: Block moving with angled force

1. Jun 22, 2013

### Robertoalva

1. The magnitude of the vectors F is 18 N, the force on the right is applied at an angle 63◦ and the the mass of the block is 35 kg. If the surface is frictionless, what is the magnitude of the resulting acceleration?

2. Relevant equations
F=ma

3. The attempt at a solution

so they are asking me for resultant acceleration, this tells me that i have to treat this as a vector problem right? then:

Fx= 18N
Fy=m*a*cosθ
a=sqrt(ax^2 +ay^2)

am I right?

2. Jun 22, 2013

### serllus reuel

the resulting motion is purely horizontal as the y-component of the force is not enough to overcome the weight of the block, which is 35 kg, so weighs just under 350 N.

another hint: use a=f/m, not f=ma as you are looking for acceleration. remember, x-direction only. Also check to see that your trig is correct. soh cah toa

3. Jun 22, 2013

### Robertoalva

F1= 18N
F2=m*a*sinθ

now i am right? if so then i can use a1=m/F1 ?

4. Jun 22, 2013

### barryj

Not quite. I don't see an accurate expression of Fx.
When you get it, then a = Fx/m

5. Jun 23, 2013

### serllus reuel

in F=ma (or a=F/m), F means the net force in a given direction, a means the acceleration in that direction, and m is the mass of the object being moved. In your statement of the problem, it seems that the TOTAL force is 18N, acting at an angle. You must break this down into x and y components using trig. Since it is quite obvious that the block will not be lifted off the surface, only the acceleration in the x direction needs to be find.

6. Jun 23, 2013

### TSny

The wording of the problem seems to me to suggest that there is more than one force of magnitude 18 N acting on the block. If so, what are the directions of the other force(s)?