Electromagnets are made up of soft iron because soft iron has
Correct answer: C. Low retentivity and low coercive force
- A. Low retentivity and high coercive force
- B. High retentivity and high coercive force
- C. Low retentivity and low coercive force
- D. High retentivity and low coercive forces
Explanation
Electromagnets are made of soft iron because it has low retentivity and low coercive force, meaning it can be easily magnetised and demagnetised. This property is crucial for electromagnets, which need to turn on and off easily. Soft iron quickly loses its magnetism when the electric current is removed, making it ideal for this purpose. Option A is incorrect because high coercive force would make the material difficult to demagnetise. Option B is unsuitable due to both high retentivity and high coercive force, characteristics of permanent magnets. Option D is incorrect because high retentivity means the material would not lose its magnetism easily, which is not desired for electromagnets.
Last updated
About Physics of Solids
Solids are compared through crystal structure, amorphous arrangement, elasticity, plastic deformation, stress, strain and Young’s modulus. Electrical behavior depends on available charge carriers and band structure, so conductors, insulators and semiconductors must be distinguished from mechanical properties such as strength, stiffness and brittleness.
Practise Physics of Solids
320 free Physics of Solids MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Physics questions like this
Physics is on 9 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
Related questions
A 4.0 m long wire is subjected to stretching force and its length increases by 40 cm. The percent elongation which the wire undergoes is:
A ball falling in a lake of 200 m shows a decrease of 0.1% in its volume. The bulk modulus of elasticity of the material of the ball is: (take g = 10 m/s²)
A ball falling in a lake of 200 m shows a decrease of 0.1% in its volume. The bulk modulus of elasticity of the material of the ball is: (take g =10 m/s2)
A block weighing 40 kg extends a spring by 0.16m from its unscratched position. What is the value of k?
A body floats in a liquid contained in a beaker. The whole system, as shown, falls freely under gravity. The upthrust on the body due to the liquid is: