PHYSICS

PHYSICS

What is the dimensional formula of electrical conductance ( G = 1/R ), where R is resistance with SI unit kg m² s^{-3 A^

Given: What is the dimensional formula of electrical conductance ( G = 1/R ), where R is resistance with SI unit kg m² s^{-3 A^{-2 ? These values define the system as per NCERT data. Formula: [R] = kg m² s^{-3 A^{-2 = [M L² T^{-3 A^{-2]. This is standard NCERT relation. Substitution & Calculation: [G] = 1 / [R] = [M^{-1 L^{-2 T³ A²] . Result: The computed value matches expected outcome and confirms correct choice as per NCERT.

Ref: NCERT Physics Textbook for Class XI and XII, Chapter: Relevant Physics topic covering fundamental principles,

View Details

PHYSICS

A copper plate has an area of 0.8 m² at 60° C . What is the decrease in area when cooled to 10° C ? ( α_l = 1.7 × 10⁻⁵K^

Given: A copper plate has an area of 0.8 m² at 60° C . What is the decrease in area when cooled to 10° C ? ( α_l = 1.7 × 10⁻⁵K^{-1 ) These values define the system as per NCERT data. Formula: Given: A_0 = 0.8 m², Δ T = 10 - 60 = -50° C, α_l = 1.7 × 10⁻⁵K^{-1. This is standard NCERT relation. Substitution & Calculation: Δ A = A_0 × 2 α_l Δ T = 0.8 × 2 × 1.7 × 10⁻⁵ × (-50) . Δ A = 0.8 × 3.4 × 10⁻⁵ × (-50) = -0.00136 m² (decrease of 0.00136 m² ). Result: The computed value matches expected outcome and confirms correct choice as per NCERT.

Ref: NCERT Physics Textbook for Class XI and XII, Chapter: Relevant Physics topic covering fundamental principles,

View Details

PHYSICS

A solenoid of 250 turns and length 0.8 m induces an emf of 0.75 V in a nearby coil when its current changes from 0 to 2.

Given: A solenoid of 250 turns and length 0.8 m induces an emf of 0.75 V in a nearby coil when its current changes from 0 to 2.5 A in 0.25 s. What is the mutual inductance? These values define the system as per NCERT data. Formula: varepsilon = M Δ I/Δ t. This is standard NCERT relation. Substitution & Calculation: Δ I = 2.5 - 0 = 2.5 A, Δ t = 0.25 s . M = fracvarepsilonΔ I/Δ t = frac0.752.5/0.25 = 0.75/10 = 0.075 H . Result: The computed value matches expected outcome and confirms correct choice as per NCERT.

Ref: NCERT Physics Textbook for Class XI and XII, Chapter: Relevant Physics topic covering fundamental principles,

View Details

PHYSICS

The magnetic potential energy of a dipole with m = 0.8 A m² in a field B = 0.25 T at 180° is:

Given: The magnetic potential energy of a dipole with m = 0.8 A m² in a field B = 0.25 T at 180° is: These values define the system as per NCERT data. Formula: U_m = -m B cosθ. This is standard NCERT relation. Substitution & Calculation: Given: m = 0.8 A m², B = 0.25 T, θ = 180°, cos 180° = -1 . Substitute: U_m = -0.8 × 0.25 × (-1) = 0.2 J . Result: The computed value matches expected outcome and confirms correct choice as per NCERT.

Ref: NCERT Physics Textbook for Class XI and XII, Chapter: Magnetism and Matter, Topic: Magnetic potential energy U = -m·B, dipole in magnetic field at 180°. The section explains definitions, governing laws, formulas like μ₀ = 4π × 10⁻⁷ T·m/A, units and illustrative examples.

View Details

PHYSICS

A long wire carries 20 A . At what distance from the wire is the magnetic field 4 × 10⁻⁶T ? ( μ_0 = 4 π × 10⁻⁷T m/A )

Given: A long wire carries 20 A . At what distance from the wire is the magnetic field 4 × 10⁻⁶T ? ( μ_0 = 4 π × 10⁻⁷T m/A ) These values define the system as per NCERT data. Formula: B = μ_0 I/2 π r, so r = μ_0 I/2 π B. This is standard NCERT relation. Substitution & Calculation: r = frac4 π × 10⁻⁷ × 202 π × 4 × 10⁻⁶= frac8 × 10⁻⁶⁸ × 10⁻⁶= 1 m . Result: The computed value matches expected outcome and confirms correct choice as per NCERT.

Ref: NCERT Physics Textbook for Class XI and XII, Chapter: Relevant Physics topic covering fundamental principles,

View Details

PHYSICS

A 6 kg mass falls from 4 m onto a spring ( k = 1500 N/m ). What is the maximum compression? (Take g = 10 m/s² )

Given: A 6 kg mass falls from 4 m onto a spring ( k = 1500 N/m ). What is the maximum compression? (Take g = 10 m/s² ) These values define the system as per NCERT data. Formula: Potential energy mgh = 6 × 10 × 4 = 240 J. This is standard NCERT relation. Substitution & Calculation: Spring energy 1/2 k x_m² = 240 Rightarrow 750 x_m² = 240 Rightarrow x_m = sqrt0.32 approx 0.566 m . Result: The computed value matches expected outcome and confirms correct choice as per NCERT.

Ref: NCERT Physics Textbook for Class XI and XII, Chapter: Relevant Physics topic covering fundamental principles,

View Details

PHYSICS

A particle in SHM has an amplitude of 12 cm and a period of 1.2 s . What is its maximum velocity? (Take π = 3.14 )

Given: A particle in SHM has an amplitude of 12 cm and a period of 1.2 s . What is its maximum velocity? (Take π = 3.14 ) These values define the system as per NCERT data. Formula: Maximum velocity: v_{max = A omega. This is standard NCERT relation. Substitution & Calculation: omega = 2π/T = 2 × 3.14/1.2 approx 5.23 rad/s . A = 0.12 m . v_{max = 0.12 × 5.23 approx 0.628 m/s . Result: The computed value matches expected outcome and confirms correct choice as per NCERT.

Ref: NCERT Physics Textbook for Class XI and XII, Chapter: Oscillations, Topic: SHM, amplitude, period, maximum velocity v_max = Aω and SHM characteristics. The section explains definitions, governing laws, formulas like μ₀ = 4π × 10⁻⁷ T·m/A, units and illustrative examples.

View Details

PHYSICS

A solenoid with mutual inductance 0.18 H has a current change of 5 A/s in the primary coil. What is the induced emf in t

Given: A solenoid with mutual inductance 0.18 H has a current change of 5 A/s in the primary coil. What is the induced emf in the secondary coil? These values define the system as per NCERT data. Formula: varepsilon = M dI/dt = 0.18 × 5 = 0.9 V .. This is standard NCERT relation. Substitution & Calculation: Substituting values and simplifying step by step as per NCERT method. Result: The computed value matches expected outcome and confirms correct choice as per NCERT.

Ref: NCERT Physics Textbook for Class XI and XII, Chapter: Relevant Physics topic covering fundamental principles,

View Details

PHYSICS

A wire has a resistance of 30 Ω at 25° C and 31.5 Ω at 75° C . What is the temperature coefficient of resistivity?

Given: A wire has a resistance of 30 Ω at 25° C and 31.5 Ω at 75° C . What is the temperature coefficient of resistivity? These values define the system as per NCERT data. Formula: Use: R_t = R_0 [1 + α (T - T_0)]. This is standard NCERT relation. Substitution & Calculation: Substitute: 31.5 = 30 [1 + α (75 - 25)] . Solve: 31.5 = 30 + 1500α Rightarrow 1500α = 1.5 Rightarrow α = 1.5/1500 = 1.0 × 10⁻³°C^{-1 . Result: The computed value matches expected outcome and confirms correct choice as per NCERT.

Ref: NCERT Physics Textbook for Class XI and XII, Chapter: Current Electricity, Topic: Temperature dependence of resistance, R_t = R₀[1+α(T-T₀)], temperature coefficient α calculation. The section explains definitions, governing laws, formulas like μ₀ = 4π × 10⁻⁷ T·m/A, units and illustrative examples.

View Details

PHYSICS

Two parallel wires 0.11 m apart carry currents of 6 A and 2 A in the same direction. What is the force per unit length b

Given: Two parallel wires 0.11 m apart carry currents of 6 A and 2 A in the same direction. What is the force per unit length between them? ( μ_0 = 4 π × 10⁻⁷T m/A ) These values define the system as per NCERT data. Formula: Force per unit length f = μ_0 I_1 I_2/2 π d. This is standard NCERT relation. Substitution & Calculation: f = frac4 π × 10⁻⁷ × 6 × 22 π × 0.11 = frac48 × 10⁻⁷⁰.22 = 2.18 × 10⁻⁶N/m . Result: The computed value matches expected outcome and confirms correct choice as per NCERT.

Ref: NCERT Physics Textbook for Class XI and XII, Chapter: Relevant Physics topic covering fundamental principles,

View Details

PHYSICS

What is the kinetic energy of a 150 kg satellite at 3 R_E from Earth’s nter? ( M_E = 6 × 10²⁴kg, R_E = 6.4 × 10⁶m, G = 6

Given: What is the kinetic energy of a 150 kg satellite at 3 R_E from Earth’s nter? ( M_E = 6 × 10²⁴kg, R_E = 6.4 × 10⁶m, G = 6.67 × 10⁻¹¹N m²/kg² ) These values define the system as per NCERT data. Formula: K = G M_E m/2 r. This is standard NCERT relation. Substitution & Calculation: r = 3 R_E = 1.92 × 10⁷m . K = frac6.67 × 10⁻¹¹ × 6 × 10²⁴ × 1502 × 1.92 × 10⁷. K = frac6.003 × 10¹⁶³.84 × 10⁷approx 1.56 × 10⁹J . Result: The computed value matches expected outcome and confirms correct choice as per NCERT.

Ref: NCERT Physics Textbook for Class XI and XII, Chapter: Relevant Physics topic covering fundamental principles,

View Details

PHYSICS

A 0.9 g drop falls from 150 m and hits the ground at 13 m/s . What is the work done by air resistance? (Take g = 10 m/s²

Given: A 0.9 g drop falls from 150 m and hits the ground at 13 m/s . What is the work done by air resistance? (Take g = 10 m/s² ) These values define the system as per NCERT data. Formula: Work by gravity W_g = mgh = 0.0009 × 10 × 150 = 1.35 J. This is standard NCERT relation. Substitution & Calculation: Final K = 1/2 × 0.0009 × 13² = 0.07605 J . K_f = W_g + W_r Rightarrow 0.07605 = 1.35 + W_r Rightarrow W_r = -1.27395 J approx -1.27 J . Result: The computed value matches expected outcome and confirms correct choice as per NCERT.

Ref: NCERT Physics Textbook for Class XI and XII, Chapter: Relevant Physics topic covering fundamental principles,

View Details