Explanation

The speed of sound is greater in solids because they have a higher density and elasticity compared to liquids and gases.

This allows sound waves to travel faster through solids

Due to the closer proximity of molecules and their stronger intermolecular forces, which facilitate the rapid transfer of vibrational energy. 

Explanation

 The moment of inertia of a solid sphere is (2/5)MR^2, where M is the mass and R is the radius.

This formula applies when the axis of rotation passes through the center of the sphere. 

Explanation

 When a rigid body rotates around a fixed axis, all points on the body have the same angular speed, but not the same linear speed.

The linear speed of a point is directly proportional to its distance from the axis of rotation; points farther from the axis move faster

Explanation

The average daily human energy intake is roughly 2000-2500 kilocalories.

One liter of petrol contains approximately 34.2 Megajoules (MJ) of energy, equivalent to roughly 8342 kilocalories.

Therefore, 1/4 liter of petrol has about 8.55 MJ of energy, which is closer to the daily human energy needs than the other options. 

Explanation

The area of the parallelogram formed by two adjacent sides, A and B, with an angle θ between them is given by the formula: Area = |A||B|sin(θ).

This is equivalent to the magnitude of the cross product of the vectors A and B, which can be written as |A x B|. 

Explanation

Two light waves that are not coherent cannot produce interference.

Interference requires that the light waves maintain a constant phase relationship, which is a characteristic of coherent sources.

Non-coherent sources have fluctuating phase differences, leading to the wash-out of interference patterns.

Explanation

The absolute uncertainty in a measuring instrument is half of the smallest division (or the least count) of the instrument.

This value represents the potential error in a measurement due to the instrument's limitations. 

Explanation

A body is in translational equilibrium when the vector sum of all forces acting on it is zero, meaning ∑F = 0.

This implies the sum of forces in both the x and y directions are also zero, i.e., ∑Fx = 0 and ∑Fy = 0.

The statement ∑τ = 0 is related to rotational equilibrium, not translational equilibrium.

The condition ∑β = 0 is not standard terminology in physics.

Explanation

An alternative unit to kg ms⁻¹ is Ns (Newton-second).

This is because 1 N = 1 kg⋅m⋅s⁻², and multiplying by seconds gives Ns = kg⋅m⋅s⁻¹. 

Explanation

The correct equation representing Heisenberg's uncertainty principle is A) Δx. Δp ≥ ħ/2. 

This equation relates the uncertainty in position (Δx) to the uncertainty in momentum (Δp),

Where "ħ" is the reduced Planck constant.