A single reflection, like shouting at the side of a mountain and hearing
your voice come back to you, is an 'echo'.
Multiple reflection, like clapping your hands once inside a large room,
is 'reverberation'.
Material that is not attracted to metal
Answer:
Physical quantity is a physical property of an object or material that can be expressed by magnitude and unit.
The derived physical quantities are the type of physical quantities which can be expressed or defined by other physical quantities, called the base quantities. Example: Area, Volume, Velocity
Area- SI Unit: m², U.S. Customary unit: acre
Volume- SI Unit: m³, U.S. Customary unit: cubic inch
Velocity- SI Unit: m/s, U.S. Customary unit: ft/s
Ignoring air resistance, the bullet's horizontal velocity is constant:

In 1.3 seconds, we can expect it to travel
