Get premium membership and access questions with answers, video lessons as well as revision papers.

Figure 9 shows the graph of the relationship between current I and potential difference V for two tungsten filament lamps X and Y. The normal working voltages for the lamp X and lamp Y are 2.5 V and 3.0 V respectively.

      

Figure 9 shows the graph of the relationship between current I and potential difference V for two tungsten filament lamps X and Y. The normal working voltages for the lamp X and lamp Y are 2.5 V and 3.0 V respectively.
physics5232017318.jpg
(a) Explain the change in the shape of the curves as the current increases.
(b) Determine the resistance of the lamps X at the normal working voltage.
(c) The lamps are now connected in a series circuit in which a current of 0.4 A flows. Find the potential differences across lamp Y.

  

Answers


John
(a) An increase in current causes an increase in temperature which in turn causes an increase in resistance.

(b) R = $\frac{V}{I} = \frac{2.5}{1.2}$ = 2.08 ohms

(c) From the graph, a current of 0.4 A corresponds to a p.d. of 1 V
johnmulu answered the question on May 23, 2017 at 12:24


Next: What are the conditions governing the rule against bias in the process of administration of justice in Kenya?
Previous: What are the principles of the rule of law?

View More Physics Questions and Answers | Return to Questions Index


Learn High School English on YouTube

Related Questions