A nichrome wire has a resistance of $10\, \Omega$. Find the resistance of another nichrome wire, whose length is three times and area of cross-section four times the first wire.
A nichrome wire has a resistance of $10\, \Omega$. Find the resistance of another nichrome wire, whose length is three times and area of cross-section four times the first wire.
Resistance $( R )$ of first wire $=\frac{\rho l}{ A }$
Resistance $\left( R ^{\prime}\right)$ of second wire $=\frac{\rho \times 3 l}{4 A }=\frac{3 \rho l}{4 A }$
So the resistance of the second wire is threefourth the resistance of the first wire $i . e, 7.5 \Omega$.
Similar Questions
$(a)$ Calculate the resistance of the wire using the graph.
$(b)$ How many $176 \,\Omega$ resistors in parallel are required to carry $5\, A$ on a $220\, V$ line ?
$(c)$ Define electric power. Derive relation between power, potential difference and resistance.
$(a)$ Calculate the resistance of the wire using the graph.
$(b)$ How many $176 \,\Omega$ resistors in parallel are required to carry $5\, A$ on a $220\, V$ line ?
$(c)$ Define electric power. Derive relation between power, potential difference and resistance.
What makes the electric current to flow through an electrolyte?
What makes the electric current to flow through an electrolyte?
What is electrical resistivity of a material? What is its unit? Describe an experiment to study the factors on which the resistance of conducting wire depends.
What is electrical resistivity of a material? What is its unit? Describe an experiment to study the factors on which the resistance of conducting wire depends.
There are two electric bulbs, $(i)$ marked $60\, W$, $220\, V$ and $(ii)$ marked $100 \,W , 220 \,V .$ Which one of them has higher resistance ?
There are two electric bulbs, $(i)$ marked $60\, W$, $220\, V$ and $(ii)$ marked $100 \,W , 220 \,V .$ Which one of them has higher resistance ?
State Joule's law of heating and write its mathematical form.
State Joule's law of heating and write its mathematical form.