Explanation

Vocal cords in females are generally shorter and thinner.

These characteristics contribute to the higher pitch of female voices compared to males.

Males vocal cords are longer and thicker.

Explanation

• Infrared waves are used in night vision equipment.
• They detect heat emitted by objects.
• It allowing visibility in low-light conditions.

Explanation

• JPEG (Joint Photographic Experts Group) is a file format used for images, not text documents.
• It's commonly used for photos and graphics.

The file extensions suitable for MS Word files:

• .doc: An older file format used by MS Word (up to version 2003).
• .rtf: Rich Text Format, a file format that can be opened by MS Word and other word processing software.
• .docx: The current file format used by MS Word (version 2007 and later).

Explanation

The degrees of freedom refer to the number of independent ways a gas molecule can store energy.

For a monoatomic gas (e.g., noble gases like helium, neon, argon):

• It has only translational motion along the x, y, and z axes.
• There are no rotational or vibrational degrees of freedom.

Thus, the total degrees of freedom for a monoatomic gas is 3 (one for each spatial direction: x, y, and z).

Explanation

Given:

Initial efficiency (η₁) = 50% = 0.5

Initial cold body temperature (T₁) = 17°C = 290 K

Initial hot body temperature (T₂) = unknown

We know that the efficiency of a Carnot engine is:

η = 1 - (T₁ / T₂)

0.5 = 1 - (290 K / T₂)

T₂ = 580 K

Now, the hot body temperature is increased by 145°C:

New hot body temperature (T₂') = 580 K + 145°C = 725 K

New efficiency (η₂) is:

η₂ = 1 - (T₁ / T₂')

= 1 - (290 K / 725 K)

≈ 0.6

New efficiency (η₂) is approximately 60%.

Explanation

Explanation

Explanation

Given:

Energy of photon (E) = 4.1 MeV

The total energy available for the electron and positron is:

E - 2 × 0.511 MeV = 4.1 MeV - 1.022 MeV = 3.078 MeV

Since the electron and positron share the energy equally, the kinetic energy of the electron is:

3.078 MeV / 2 = 1.539 MeV

Adding the rest mass energy of the electron (0.511 MeV), we get:

Energy of electron = 1.539 MeV + 0.511 MeV = 2.05 MeV

Explanation

Explanation