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Bulk Modulus and Compressibility

Questions on bulk modulus and compressibility, focusing on how materials change volume under pressure. Includes problems on pressure effects and material behavior.

23 questions

A steel rod of radius 0.01m and length 1.5m is subjected to a tensile force producing a stress of 4×107N/m2. What is the

Stress: Stress = FA. Area: A = πr2 = 3.14×(0.01)2 = 3.14×10−4m2. Force: F = Stress×A = 4×107×3.14×10−4 = 1.256×104N. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 1.256×104N. This satisfies dimensional consistency and physical conditions given, so option A is scientifically correct.

Ref: University Physics, Chapter 17: Thermal Expansion.

A brass rod of radius 0.008m and length 1.0m is subjected to a tensile force producing a stress of 5×107N/m2. What is th

Stress: Stress = FA. Area: A = πr2 = 3.14×(0.008)2 = 3.14×6.4×10−5≈2.01×10−4m2. Force: F = Stress×A = 5×107×2.01×10−4≈1.005×104N. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 1.005×104N. This satisfies dimensional consistency and physical conditions given, so option A is scientifically correct.

Ref: NCERT Class 11 Physics, Thermal Properties and Gravitation.

A steel wire of length 2.6m and cross-sectional area 2×10−6m2 is stretched by a force of 400N. If the Young's modulus of

Young's modulus: Y = FLAΔL. Rearrange: ΔL = FLAY. Substitute: ΔL = 400×2.62×10−6×2×1011 = 10404×105 = 2.6×10−3m = 2.6mm. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 2.6mm. This satisfies dimensional consistency and physical conditions given, so option B is scientifically correct.

Ref: University Physics, Chapter 17: Thermal Expansion.

A brass wire of length 2.4m and cross-sectional area 3×10−6m2 is stretched by a force producing a stress of 5×107N/m2. I

Young's modulus: Y = StressStrain. Strain: Strain = StressY = 5×1079×1010≈5.56×10−4. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 5.56×10−4. This satisfies dimensional consistency and physical conditions given, so option B is scientifically correct.

Ref: NCERT Class 11 Physics, Thermal Properties and Gravitation.

A brass wire of length 1.6m and cross-sectional area 2×10−6m2 is stretched by a force producing a stress of 4×107N/m2. I

Young's modulus: Y = StressStrain. Strain: Strain = StressY = 4×1079×1010≈4.44×10−4. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 4.44×10−4. This satisfies dimensional consistency and physical conditions given, so option D is scientifically correct.

Ref: NCERT Class 11 Physics, Thermal Properties and Gravitation.

A glass slab of volume 0.01m3 is subjected to a hydraulic pressure of 2×106N/m2. If the bulk modulus of glass is 3.7×101

Bulk modulus: B = −pΔVV. Rearrange: ΔVV = −pB = −2×1063.7×1010≈−5.41×10−5. Change in volume: ΔV = ΔVV×V = −5.41×10−5×0.01≈−5.41×10−7m3. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 5.41×10−7m3. This satisfies dimensional consistency and physical conditions given, so option C is scientifically correct.

Ref: NCBI Bookshelf, Ideal Gas Law: P1V1/T1 = P2V2/T2.

An aluminium block of dimensions 0.6m×0.4m×0.2m is subjected to a shearing force of 8×104N. If the shear modulus of alum

Shear modulus: G = F/AΔx/L. Rearrange: Δx = FLAG. Area: A = 0.6×0.4 = 0.24m2, L = 0.2m. Substitute: Δx = 8×104×0.20.24×2.5×1010 = 160006×109≈2.67×10−6m. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 2.67×10−6m. This satisfies dimensional consistency and physical conditions given, so option B is scientifically correct.

Ref: NCERT Class 11 Physics, Thermal Properties and Gravitation.

A steel wire of length 2.7m and cross-sectional area 2×10−6m2 is stretched by 0.54mm. If the Young's modulus of steel is

Strain: Strain = ΔLL = 0.54×10−32.7 = 2×10−4. Young's modulus: Y = StressStrain. Stress: Stress = Y×Strain = 2×1011×2×10−4 = 4×107N/m2. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 4×107N/m2. This satisfies dimensional consistency and physical conditions given, so option C is scientifically correct.

Ref: University Physics, Chapter 17: Thermal Expansion.

A water sample of volume 1litre is compressed by a pressure of 1×106N/m2. If the bulk modulus of water is 2.2×109N/m2, w

Bulk modulus: B = −pΔVV. Rearrange: ΔVV = −pB = −1×1062.2×109≈−4.55×10−4. Magnitude: 4.55×10−4. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 4.55×10−4. This satisfies dimensional consistency and physical conditions given, so option D is scientifically correct.

Ref: NCBI Bookshelf, Ideal Gas Law: P1V1/T1 = P2V2/T2.