Science All General Science Aptitude

Density is defined as mass per unit volume (\(Density = \dfrac{Mass}{Volume}\)). If the mass of a solid is doubled while its volume remains constant, the density will double.

Therefore, the correct answer is:

A. becomes two times

Fats and oils become rancid due to C. oxidation. When fats and oils are exposed to air, they undergo oxidation, a chemical reaction in which the fat molecules react with oxygen. This process can lead to the development of unpleasant odors and flavors, as well as changes in the nutritional quality of the fats and oils.

The forces between two bodies, according to Newton's third law of motion, are always B. equal and in the opposite direction. For every action, there is an equal and opposite reaction. When one body exerts a force on another, the second body exerts an equal force in the opposite direction on the first body.

The correct statement is:

D. The Mass and Weight of the body remain the same in different places.

Mass is a scalar quantity and does not change regardless of location, while weight is a vector quantity dependent on gravity. The mass of an object remains constant, but its weight can vary depending on the local gravitational field strength. However, the mass itself is independent of location.

The equation that relates initial velocity (\(u\)), acceleration (\(a\)), time (\(t\)), and final velocity (\(v\)) is given by:

\[v = u + at\]

Given that \(u = 0 \ m/s\), \(a = 5 \ m/s^2\), and \(t = 5 \ s\), you can substitute these values into the equation:

\[v = (0 \ m/s) + (5 \ m/s^2 \times 5 \ s)\]

\[v = 25 \ m/s\]

Therefore, the correct answer is:

B. \(25 \ m/s\)

The SI unit of electric charge is D. Coulomb

On applying a constant force to a body, it moves with uniform B. Speed.

Uniform speed means the body is moving at a constant rate without changing its velocity. If the force is applied in the direction of motion and the net force is constant, the body will experience constant acceleration, leading to uniform speed.

‘Gallon’ is commonly used C. As a measure of volume. In various systems of measurement, a gallon is a unit of volume, typically used to measure liquids. The exact size of a gallon can vary based on the system of measurement (e.g., U.S. gallon, imperial gallon).

On applying a constant force to a body, it moves with uniform D. Acceleration. If a constant force is applied to a body, it will undergo uniform acceleration, assuming no other forces are acting on it. The relationship between force, mass, and acceleration is given by Newton's second law of motion:

F=ma,
where
F is the force applied,
m is the mass of the object, and
a is the acceleration.

Resistance (R) = 5 ?
The Resistance of wire = R = p L / A
When the wire is doubled, its length becomes half, and the area of cross-section is doubled = R = p L / A = p L/2 / 2A = 1/4 p L / A = 1.25 ? New Resistance