Calculate the work done by the applied force accelerating a 2 kg object at 3 m/s/s over 4 m if there is a 2.5 frictional force of resistance. I calculated using F=ma=6N; then net force = 6N-2.5N=3.5 N so W=fd=14J. Did I do this correctly? Thanks
work done=2.5*3 + 2*3*4 I get more than you. You did the accelerating force only, you have to add the force working against friction
Help!I'm really lost on this one.
correction: I mistyped the distance on friction.
Workdone=2.5*4+2*3*4 joules.
To calculate the work done by a force, you need to multiply the magnitude of the force by the displacement in the direction of the force. In this case, you have correctly calculated the net force acting on the object, which is 3.5 N (6 N - 2.5 N).
Now, to find the work done, you need to multiply the net force by the displacement. The displacement given in the problem is 4 m. So, using the formula for work (W = Fd), the work done by the applied force is:
W = 3.5 N * 4 m = 14 J
Therefore, your calculation is correct. The work done by the applied force is indeed 14 Joules (J).
However, it's worth mentioning that you made a small mistake in your calculation of the net force. The magnitude of the net force should be F = ma = (2 kg)(3 m/s²) = 6 N, as you correctly mentioned. But the correct calculation for the net force should be 6 N - 2.5 N = 3.5 N, as you initially mentioned.