Cause & Effect: Ammeter Resistance & Circuit Current

  • Thread starter Thread starter phyphysics
  • Start date Start date
  • Tags Tags
    Cause
AI Thread Summary
The discussion revolves around a physics question regarding the relationship between an ammeter's resistance and its effect on circuit current. The first statement asserts that an ammeter has very low resistance, while the second claims that the current is negligibly affected when the ammeter is connected in series. There is confusion over whether the second statement explains the first, with some participants believing the opposite is true. Clarification suggests that the second statement is true because of the first, indicating that the ammeter's low resistance is the reason for its minimal impact on current. Overall, the question is criticized for its poor wording and ambiguity.
phyphysics
Messages
25
Reaction score
0
I have such a question in my physics book:

There are 2 statements below. Choose a if the second statement is an explanation of the first statement; otherwise, choose b :

1. Ammeter has a very small resistance.

2. The current in the circuit can be said negligibly affected when the ammeter is connected in series with it correctly.

I thought the answer should be b , as I thought that statement 1 should be the explanation of statement 2, not vice versa. But the answer said is a . Why?
 
Physics news on Phys.org
I would agree with you. Personally that's a very confusing and badly written question.

~Lyuokdea
 
Allow me to lend my support, gents. It might be a matter of semantics, though; Statement #1 is definitely the basis for Statement #2, but might not necessarily be an explanation for it. Regardless, it's a very poorly presented problem. Given the same choice that you were, I would have chosen similarly.
 
In the future I suggest interpreting it as:

Choose a if the second statement explains why the first statement is true; otherwise, choose b :
 
2 is true *because* 1 is true. The ammeter has low resistance *because* it was made that way (Aristotle's Effective Cause), not because it has a negligible effect on the current.
 
yeah. the reason that there is a negligible effect is that there is a small resistance. besides, the wording in 2 is that "it can be said". so now the question is, why can this be said?
 
Thread 'Variable mass system : water sprayed into a moving container'
Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...

Similar threads

Replies
2
Views
478
Replies
1
Views
593
Replies
6
Views
2K
Replies
4
Views
3K
Replies
10
Views
2K
Replies
14
Views
3K
Back
Top