Two students are dragging a 25.0 kg object along the hall as shown in the diagram below. If the force of friction action on the object is 5.0 N, what is the acceleration of the object? (Be sure to include direction)
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so you can add your force vectors
F_net = mass * acceleration F_net / mass = acceleration
I am in a confusion whether the object is traveling straight east or at a northeast direction because FT1 > FT2
actually the force of friction is opposite to the direction of movement
yes but the here the force of friction is less the force applied so it is moving forward
but what direction?
Wellfor one, you will be finding the force in both directions:\[\sum F_y\]\[\sum F_x\]
so first find the direction of movement, the opposite of that direction will be the friction vector
Then decide which way you want your positive direction to be before solving your equations.
Ft1 + Ft2 =< 40 cos 20 , 40 sin 20> + <-30 cos 25, -30 sin 25> = < 40 cos 20 - 30 cos 25 , 40 sin 20 - 30 sin 25>
\[\sum F_y = ma_y = T_1-T_2\]
so I found the resultant vector of vectors Ft1 and Ft2 , the magnitude and direction you can find
Fnetx = FT1x + FT2x - Ffriction = 37.59 + 21.65 - 5 = 54. 24
\[T_{1_y} = 40.0\sin (20^{\circ})\]\[T_{2_y} =25.0\sin(30.0^{\circ})\]
FT1y + FT2y = Fnety (13.68) + (-12.5) = 1.18 N
My method is the same as @perl's except broken down into net directional form
So northeast direction?
Why are you addind both of the y directions? are they being pulled the same way?
Fnet is a total of all forces and since on of them is negative force
I added them
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