Question
State the laws of resistance.
✓
Answer
Laws of resistance -
(i) Resistance of a conductor depends upon its nature of material.
(ii) Resistance of a conductor is directly proportional to its length (R $\propto l$ ).
(iii) Resistance of a conductor is imversely proportional to its area of cross-section, $\left( R \propto \frac{1}{ a }\right)$.
(i) Resistance of a conductor depends upon its nature of material.
(ii) Resistance of a conductor is directly proportional to its length (R $\propto l$ ).
(iii) Resistance of a conductor is imversely proportional to its area of cross-section, $\left( R \propto \frac{1}{ a }\right)$.
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
A metal wire of resistance $6 Ω$ is stretched so that its length is increased to twice its original length. Calculate its new resistance.
→A coin is places at the bottom of a beaker containing water (refractive index = 4/3) to a depth of 12 cm. By what height the coin appears to be raised when seen from vertically above?
When acoustic resonance takes place, a loud sound is heard. Why does this happen? Explain.
The following diagram shows three lamps and three switches 1, 2 and 3
(a) Name the switch / switches to be closed so as to light all the three lamps.
(b) How are the lamps connected: in series or in parallel?
(a) Name the switch / switches to be closed so as to light all the three lamps.
(b) How are the lamps connected: in series or in parallel?
A coolie X Carrying a load on his head climbs up a slope and another coolie Y carrying the identical load on his head move the same distance on a frictionless horizontal platform. Who does more work? Explain the reason.
A block and tackle system has 5 pulleys. If an effort 0f 1000 N is needed in the downward direction to raise a load of 4500 N, calculate:
(a) the mechanical advantage
(b) the velocity ratio, and
(c) the efficiency of the system
(a) the mechanical advantage
(b) the velocity ratio, and
(c) the efficiency of the system
State reason why is mechanical advantage less than the velocity ratio for an actual machine.
How is it possible to detect the filling of a bottle under a water tap by hearing the sound at a distance?
State Fleming's left hand rule.
State the factors on which the centre of gravity of a body depends.