C. Thick wire and cold temperature.
Explanation:
The resistance of a wire is given by: R = (ρL)/A
where ρ is the resistivity of the material, L is the length of the wire, A is the cross-sectional area of the wire.
From the formula, we see that the thicker the wire, the larger A, therefore the smaller the resistivity. so, a thick wire will have lower resistivity.
Moreover, the resistance of a wire increases with the temperature. In fact, high temperatures mean more motion of the atoms/electrons inside the wire, so more resistance to the flow of current through it. Therefore, colder temperature means lower resistance.
So, the correct option is thick wire and cold temperature.
GIVEN:
60 beats per minute
21 beats per minute
find x= how fast would an astronaut be flying away
1 x
----- * ------ = (60x = 21) -------> 60x = 21 ------------> x= 0.35
60 21 ------- -----
60 60
The answer is 0.35 seconds which refers to how fast would an astronaut be flying away from the earth if he has a heart rate of 21 beats/min.
Answer:
(C) deflected toward the top of the page.(
Explanation:
We can answer this problem by using Fleming's Left Hand Rule. By doing so, we have to place:
- The index finger of the left hand in the direction of the magnetic field
- The middle finger of the left hand in the direction of the particle's velocity
- The thumb will give the direction of the force, and therefore the deflection of the proton
In this problem, we have:
- Magnetic field direction: into the page --> index finger
- Proton's velocity: to the right --> middle finger
By doing so, we observe that the thumb points towards the top of the page: therefore, the correct answer is
(C) deflected toward the top of the page.