Answer:
T= 4.24sec
Explanation:
We are going to use the formula below to calculate.
Where T is period
L is length of rod
g is acceleration due to gravity = 
From the problem, the rod is pivoted at 1/4L which means that three quarter of the rod was used for the oscillation. lets call this 
= 4.4625m
thus 
T= 4.24sec
Answer:
(1) A sound wave a mechanical wave because mechanical waves rely on particle interaction to transport their energy, they cannot travel through regions of space that are void of particles. Sound is a mechanical wave and cannot travel through a vacuum. These particle-to-particle, mechanical vibrations of sound conductance qualify sound waves as mechanical waves. Sound energy, or energy associated with the vibrations created by a vibrating source, requires a medium to travel, which makes sound energy a mechanical wave. The answer is(B) it travels in the medium.
(2) An ocean wave is an example of a mechanical transverse wave
The compression is the part of the compressional wave where the particles are crowded together. The rarefaction is the part of the compressional wave where the particles are spread apart. The answer is (C) Compression.
Answer:
When an object is balanced, about a pivot, the total clockwise moment must be equal to the total anticlockwise moment about that pivot.
Hope that helps.
Answer:
1. the force which can be felt or act only when two objects are in contact is known as contact force.
for example: frictional force, muscular force,
tension, air resistance .
2. the force which can be felt or act even when two objects are in contact or not is known as non-contact force.
for example: magnetic force, gravitational force, electrostatic force.
