- #1
ohms law
- 70
- 0
I'm having a little trouble conceptualizing calculations of force. The problem statement was:
An object in space with a mass of 68 kg is propelled forward at a constant force ([itex]\vec{F}[/itex]) for 3.0 seconds. After 3.0 s, the object has moved 2.25 m. find [itex]\vec{F}[/itex].
I can regurgitate the proper answer (34 N) by finding [itex]a_{x}=2 \Delta x/t^{2} = 0.50 m/s^{2}[/itex] and [itex]\vec{F}=ma_{x} = (68kg)(0.50 m/s^{2}) = 34 N[/itex].
the problem is that my intuition tells me that it should be:
t = 3.0s
m = 68 kg
Δx = 2.25 m
So since [itex]N = kg \cdot m / s^{2}[/itex], [itex]N = 68 kg \cdot 2.25 m / 3.0 s^{2} = 17 N[/itex], which is obviously wrong. But, does that actually mean something else? Is that some sort of instantaneous value or something, or is it completely meaningless?
An object in space with a mass of 68 kg is propelled forward at a constant force ([itex]\vec{F}[/itex]) for 3.0 seconds. After 3.0 s, the object has moved 2.25 m. find [itex]\vec{F}[/itex].
I can regurgitate the proper answer (34 N) by finding [itex]a_{x}=2 \Delta x/t^{2} = 0.50 m/s^{2}[/itex] and [itex]\vec{F}=ma_{x} = (68kg)(0.50 m/s^{2}) = 34 N[/itex].
the problem is that my intuition tells me that it should be:
t = 3.0s
m = 68 kg
Δx = 2.25 m
So since [itex]N = kg \cdot m / s^{2}[/itex], [itex]N = 68 kg \cdot 2.25 m / 3.0 s^{2} = 17 N[/itex], which is obviously wrong. But, does that actually mean something else? Is that some sort of instantaneous value or something, or is it completely meaningless?