26 public questions tagged with this topic.
L = r×p = |i^j^k^0305−20| = k^(0×(−2)−3×5) = −15k^kg m2/s. Z-component = −15kg m2/s. As per NCERT, applying relevant law/formula with correct units and sign convention leads to -15 kg m²/s. This satisfies dimensional consistency and physical conditions given, so option B is scientifically correct.
Ref: NCERT Class 11 Physics, Thermal Properties and Gravitation.
τ = r×F = |i^j^k^5204−60| = k^(5×(−6)−2×4) = k^(−30−8) = −38k^Nm. Magnitude = 38Nm. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 38 Nm. This satisfies dimensional consistency and physical conditions given, so option C is scientifically correct.
Ref: NCERT Class 11 Physics, Thermal Properties and Gravitation.
Angular momentum: L = Iω. For a solid cylinder: I = 12MR2 = 12×10×(0.5)2 = 1.25kgm2. ω = LI = 251.25 = 20rad/s. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 20 rad/s. This satisfies dimensional consistency and physical conditions given, so option B is scientifically correct.
Ref: NCERT Class 11 Physics, Thermal Properties and Gravitation.
Using the formula for the x-coordinate of the center of mass: X = m1x1+m2x2+m3x3m1+m2+m3. Masses: m1 = 2kg, m2 = 3kg, m3 = 5kg. Coordinates: x1 = 0, x2 = 4, x3 = 2. X = (2×0)+(3×4)+(5×2)2+3+5 = 0+12+1010 = 2210 = 2.2m.
Ref: NCERT Class 11 Physics, Thermal Properties and Gravitation.
L = mvr. m = 1kg, v = 4m/s, r = 0.5m. L = 1×4×0.5 = 2kg m2/s. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 2 kg m²/s. This satisfies dimensional consistency and physical conditions given, so option B is scientifically correct.
Ref: NCERT Class 11 Physics, Thermal Properties and Gravitation.
Distance to 16kg: 16−7 = 9m. U = −Gm1r1−Gm2r2. U = −6.67×10−11(87+169). U = −6.67×10−11(1.143+1.778)≈−1.95×10−10J/kg. As per NCERT, applying relevant law/formula with correct units and sign convention leads to -1.9 × 10⁻¹⁰ J/kg. This satisfies dimensional consistency and physical conditions given, so option A is scientifically correct.
Ref: Halliday & Resnick, Fundamentals of Physics, 11th ed., Chapter 13: Gravitation.
F = Gm1m2r2 is always attractive, as masses are positive and the force vector points toward each other, making option 1 correct. As per NCERT, applying relevant law/formula with correct units and sign convention leads to It is always attractive. This satisfies dimensional consistency and physical conditions given, so option A is scientifically correct.
Ref: Halliday & Resnick, Fundamentals of Physics, 11th ed., Chapter 13: Gravitation.
For elastic collision, momentum and kinetic energy conserved: m1v1+m2v2=m1v1'+m2v2' and ½m1v1²+... per NCERT. Solving gives velocities matching 6 m/s. Inelastic loses energy. So option A is correct.
Ref: NCERT Class 11 Physics > Chapter 6: Work, Energy and Power > Topic: Energy Conservation and Friction
Centripetal acceleration a_c=v²/r=4π²r/T²=4π²rf² per NCERT circular motion. Substituting r and frequency/period gives a_c value matching 0.5 Hz. Other options use incorrect r or f, so A is correct.
Ref: NCERT Class 11 Physics > Chapter 4: Motion in a Plane > Topic: Relative Motion and Plane Motion
A. As per NCERT Class 11 Chapter 2, dimensional analysis checks correctness and SI units define base and derived quantities. This principle confirms that Angular momentum is correct because its dimensions and unit match the physical quantity asked.
Ref: NCERT Class 11 Physics > Chapter 2: Units and Measurements > Topic: SI Units and Dimensional Formulae
Significant figures depend on least precise measurement. For 9.99 m (2 decimal places) minus 0.0099 m (4 decimal places), result 9.9801 m must be rounded to 2 decimal places as per subtraction rule in NCERT. So 9.98 m is correct, retaining 3 significant figures. Thus 9.98 m follows significant figure rules.
Ref: NCERT Class 11 Physics > Chapter 2: Units and Measurements > Topic: SI Units and Dimensional Formulae
Significant figures depend on least precise measurement. For 9.99 m (2 decimal places) minus 0.0099 m (4 decimal places), result 9.9801 m must be rounded to 2 decimal places as per subtraction rule in NCERT. So 9.98 m is correct, retaining 3 significant figures. Thus 3 follows significant figure rules.
Ref: NCERT Class 11 Physics > Chapter 2: Units and Measurements > Topic: SI Units and Dimensional Formulae
