Explanation

At constant temperature, the resistance (R) of a conductor is inversely related to its cross-sectional area (A). This is expressed by the formula: R = ρ × L / A

where:

• R is the resistance
• ρ (rho) is the resistivity of the material
• L is the length of the conductor
• A is the cross-sectional area

As the cross-sectional area (A) increases, the resistance (R) decreases, and vice versa. This is why thicker wires have lower resistance than thinner wires.

Explanation

Uranium-235 (U²³⁵) is a fissile isotope, meaning it readily undergoes nuclear fission when struck by a neutron.

It is commonly used in nuclear reactors and atomic bombs for this reason.

Explanation

Explanation

Explanation

Nuclear fuel cladding materials should have low neutron absorption and high melting points.

Cadmium has a high neutron absorption cross-section, making it unsuitable for cladding.

Explanation

When a car crashes into a tree, momentum is generally conserved in an isolated system (assuming no external forces).

Still, kinetic energy is not fully conserved due to energy being converted into other forms like sound, heat, and deformation of the car.

Explanation

The strength of the magnetic field around a conductor is determined by how much current is flowing.

The magnetic field is directly proportional to the current.

Explanation

• Thermal Contraction is the decrease in size (length, area, and volume) of a body due to a decrease in temperature.
• Thermal Expansion is the opposite phenomenon, where the size increases due to an increase in temperature.

Explanation

The pressure of a gas in a container is affected by:

• Temperature (increases with temperature)
• Volume (decreases with increasing volume)
• Density of gas (increases with density)

However, the material of the container does not directly affect the pressure of the gas.

Explanation

Our solar system takes approximately 250 million years to complete one orbit around the Milky Way galaxy.