Physics

The number 5.400 has four significant figures. All non-zero digits are significant, and trailing zeros after the decimal point are also significant. Therefore, the digits 5, 4, 0, and 0 are all significant, making a total of 4 significant figures. Since the original options did not include 4, the options should be corrected to include 4 as the correct answer.

Irregular flow of fluid is known as turbulent flow, characterized by chaotic changes in pressure and flow velocity. Laminar flow, streamline, and uniform flow refer to smooth, orderly fluid motion, which contrasts with turbulent flow.

A sphygmomanometer measures blood pressure statically by occluding the artery and then slowly releasing pressure to detect systolic and diastolic pressures. It does not measure blood pressure dynamically (continuously over time).

The outward force acting on a mass rotating in a circle (often called the centrifugal force in a rotating frame) is equal in magnitude to the centripetal force required to keep it moving in a circle. The centripetal force is calculated by the formula F = m*v^2/r. For a mass of 10 kg, radius 10 m, and speed 1 m/s, the force is F = 10*(1^2)/10 = 1 N. Therefore, the outward force magnitude is also 1 N. Among the given options, 1 N corresponds to option A, making it the correct answer.

The Earth completes one full rotation (2π radians) in approximately 24 hours (86400 seconds). The angular speed ω = 2π / 86400 ≈ 7.27 x 10^-5 radians/second, which matches option D.

A body has constant velocity only when it moves in a straight line with constant speed, which corresponds to a rectilinear path. Paths like elliptical, circular, or parabolic involve changes in direction or speed, so velocity is not constant.

One radian is defined as the angle subtended at the center of a circle by an arc whose length is equal to the radius of the circle. This angle is approximately 57.3 degrees, making option B correct.

The gravitational constant G has units derived from Newton's law of gravitation: F = G * (m1*m2)/r^2. Rearranging, G = F * r^2 / (m1*m2). Since force (F) is in Newtons (N), distance (r) in meters (m), and mass (m) in kilograms (kg), the units of G are N·m²/kg².

In vertical circular motion, the tension in the string varies with the position of the stone. At the lowest point, the tension is greatest because it must provide the centripetal force to keep the stone moving in a circle and also counteract the weight of the stone (gravity). The tension at the lowest point is given by T = (mv^2)/r + mg, where m is the mass, v is the speed, r is the radius, and g is the acceleration due to gravity. At the highest point, the tension is least and given by T = (mv^2)/r - mg, since gravity assists the centripetal force there. Therefore, the string is most likely to break at the lowest point where the tension is maximum.

When a body is whirled in a horizontal circle by a string, the tension in the string provides the inward (centripetal) force necessary to keep the body moving in a circular path. Neither mass, velocity, nor acceleration themselves supply the force; they influence the magnitude of the required centripetal force.

According to Bernoulli's principle, in a streamline flow, an increase in fluid velocity corresponds to a decrease in pressure. Therefore, the velocity of a fluid increases where the pressure is low.

Venus is the planet that comes closest to Earth during their orbits, making it the nearest planet to Earth on average. Mercury, while closer to the Sun, is not typically the closest planet to Earth.

A Venturi meter measures the flow speed (velocity) of a fluid by utilizing the pressure difference created by the fluid passing through a constricted section of pipe. It does not directly measure fluid pressure or density.

The equation of continuity states that A1V1 = A2V2 = constant, where A is the cross-sectional area and V is the velocity of the fluid. This constant represents the flow rate (volume flow rate), which is the volume of fluid passing through a section per unit time.

Option B, S = Vit + 1/2 at², is dimensionally correct as it represents displacement (S) as a function of initial velocity (Vi), time (t), and acceleration (a). The other options do not have consistent dimensions on both sides of the equation.

When multiplying or dividing measurements, the percentage (or relative) uncertainties are added together to find the combined uncertainty. Absolute uncertainties are not simply added or divided in these operations.

In circular motion, the linear velocity vector at any point is always tangent to the circle, indicating the direction in which the body is moving at that instant. It is neither along the axis of rotation nor directed towards or away from the center.

Centripetal force acts perpendicular to the direction of the object's displacement in circular motion, so it does no work on the object.

In reverse swing, the cricket ball moves towards the rough side rather than the shiny side. This occurs because the airflow behaves differently at high speeds, causing the ball to swing in the opposite direction to conventional swing.

After completing two full revolutions around a circle, the body returns to its starting point. Therefore, the displacement, which is the straight-line distance from the initial to the final position, is zero, while the path length is the circumference times two.

The equation of continuity is derived from the law of conservation of mass, stating that mass cannot be created or destroyed in a fluid flow, ensuring mass flow rate remains constant.

The seconds hand of a watch completes one full rotation, which is 2π radians, in 60 seconds. Therefore, its angular speed is given by the total angle divided by the time taken: ω = 2π / 60 = π/30 radians per second. This matches option C. The original correct_answer field was incorrectly set to D, but the explanation correctly identified the answer as π/30 radians per second, which corresponds to option C.

Isaac Newton formulated the inverse square law of gravitation, which states that the gravitational force between two masses is inversely proportional to the square of the distance between them. This fundamental law is a cornerstone of classical physics.

A carburettor uses the Venturi effect to reduce pressure and draw fuel into the air stream, which is explained by Bernoulli's equation. Therefore, both the Venturi meter principle and Bernoulli's equation apply to the carburettor's operation.

In simple harmonic motion, the velocity of the particle is maximum as it passes through the mean position because all the potential energy is converted into kinetic energy there. At the extreme positions, the velocity is zero as the particle changes direction.