PMS MCQs

Pressure inside the cooker increases above atmospheric pressure.
Water then boils at a higher temperature and cooks food faster.

Pitch rises as vibration frequency increases.
Low frequencies produce lower-pitched sounds.

Visible light is part of the electromagnetic spectrum.
It can travel through a vacuum.

Greater wave amplitude carries more energy.
It is generally perceived as a louder sound.

Non-luminous objects become visible when illuminated.
Reflected light enters the eyes and forms an image.

Sound waves can reflect from distant surfaces.
If the delay is sufficient, the reflected sound is heard as an echo.

Reflection from a smooth surface obeys equal incidence and reflection angles.
Both angles are measured from the normal.

A plane mirror forms a virtual image behind the mirror.
The image is upright, same-sized, and left-right reversed.

Light changes speed when moving between media.
This speed change usually causes bending, called refraction.

Light from the submerged part changes direction when leaving water.
The brain traces rays backward and sees an apparent displacement.

Spectacle lenses change the convergence of light entering the eye.
They help focus images correctly on the retina.

The iris changes the size of the pupil.
This regulates how much light enters the eye.