Join

JEE WhatsApp Group

Question 13

The resistance of a wire is 5 $$\Omega$$. Its new resistance in ohm, if stretched to 5 times of its original length will be:

Solution

For a wire:

$$R=\rho\frac{L}{A}$$

When the wire is stretched, its volume remains constant:

$$A_1L_1=A_2L_2$$

Given:

$$L_2=5L_1$$

So,

$$A_2=\frac{A_1}{5}$$

Now new resistance:

$$R_2=\rho\frac{5L_1}{A_1/5}$$

$$R_2=25\rho\frac{L_1}{A_1}$$

$$R_2=25R_1$$

Get AI Help

Video Solution

video

Create a FREE account and get:

Free JEE Mains Previous Papers PDF
Take JEE Mains paper tests

maruti sir image

Other Cracku’s Useful Resources:

JEE Questions JEE Question Bank JEE Mains Previous Papers JEE Advanced Previous Papers JEE Study Material PDF JEE Mains Mock Test JEE Advanced Mock Test JEE Daily Target

Free JEE Topicwise Questions

JEE Rotational Motion JEE Units & Measurements JEE Atomic Structure JEE Gravitation JEE Periodic Table & Periodicity JEE Statistics JEE Inverse Trigonometric Functions JEE Magnetism & Magnetic Materials JEE Sequences & Series JEE Matrices JEE Alternating Currents JEE Carboxylic Acids JEE Permutations & Combinations JEE Work, Energy & Power JEE Electromagnetic Induction JEE Electronic Devices JEE d and f-Block Elements JEE Chemical Kinetics JEE Heat Transfer JEE Three Dimensional Geometry JEE Magnetic Effects of Current JEE Hydrocarbons - Aromatic JEE Electromagnetic Waves JEE Aldehydes & Ketones JEE Hydrocarbons - Alkanes JEE Applications of Derivatives JEE Equilibrium JEE Indefinite Integration JEE Chemical Thermodynamics JEE Electrochemistry JEE Probability JEE Biomolecules JEE Continuity & Differentiability JEE Kinetic Theory of Gases JEE Vector Algebra JEE Hydrocarbons - Alkynes JEE Differential Equations JEE Current & Resistance JEE Straight Lines JEE Waves JEE Redox Reactions JEE Hydrocarbons - Alkenes JEE Determinants JEE Solutions JEE Ray Optics JEE Dual Nature of Matter & Radiation JEE Chemical Bonding & Molecular Structure JEE Complex Numbers JEE Sets, Relations & Functions JEE Electric Charges & Fields JEE Laws of Motion JEE Fluid Mechanics JEE Basic Concepts in Chemistry JEE Trigonometric Functions JEE Limits JEE Laws of Thermodynamics JEE Kinematics - 2D Motion JEE p-Block Elements (Groups 13-18)JEE Simple Harmonic Motion JEE Electric Potential & Capacitance JEE Coordination Compounds JEE JEE 2D Geometry JEE Circles JEE Definite Integration JEE EMF & Circuit Analysis JEE Surface Tension JEE Atoms & Nuclei JEE Laboratory Experiments - XI JEE Number System JEE Basic Principles of Organic Chemistry JEE Wave Optics JEE Quadratic Equations JEE Alcohols, Phenols & Ethers JEE Organic Compounds with Halogens JEE Differentiation JEE Conic Sections JEE Nitrogen-Containing Compounds JEE Elasticity JEE Practical Organic Chemistry JEE Kinematics - 1D Motion JEE Purification & Characterisation JEE Binomial Theorem

Ask our AI anything

AI can make mistakes. Please verify important information.