m = Mass of the refrigerator to be moved to third floor = 136 kg
g = Acceleration due to gravity by earth on the refrigerator being moved = 9.8 m/s²
h = Height to which the refrigerator is moved = 8 m
W = Work done in lifting the object
Work done in lifting the object is same as the gravitational potential energy gained by the refrigerator. hence
Work done = Gravitation potential energy of refrigerator
W = m g h
inserting the values
W = (136) (9.8) (8)
W = 10662.4 J
<em>An is formed when an atom loses or gains one or more electrons. Because the number of electrons in an ion is different from the number of protons, an ion does have an overall electric charge. Consider how a positive ion can form from an atom. The left side of the illustration below represents a sodium (Na) atom</em>
<h2>
Answer:Radiation-3,Conduction-1,Convection-2</h2>
Explanation:
Radiation is the transfer of heat through electromagnetic waves.
These waves do not require any medium.This is the way we get heat from sun.Radiation is the quickest mode to transfer of heat.
Conduction is the transfer of heat through collisions of atomic particles.
This phenomenon largely occurs in solids like metals.The neighbour atoms sets the atoms into random motion thereby raising the temperature.
Convection is the transfer of heat through actual movement of medium particle.
This phenomenon occurs in gases an liquids.The medium particles actually traverse through the space transferring the heat.
To solve this problem, it will be necessary to apply the concepts related to the fundamental resonance frequency in a closed organ pipe.
This is mathematically given as

For fundamental frequency n is 0, then,

When,
v = Velocity of sound
L = Length,
Rearranging to find the velocity,



Therefore the speed of sound in this gas is 416m/s
Answer:
A) a neutron pushing on another neutron.
Explanation:
Neutrons have no charge, therefore, there is no electric force among them. Protons and electrons on the other hand do have electric charge (electrons negative charge and protons positive charge) that generate electric forces between them that can be repelling forces (if the charges are of the same sign), or attractive forces (if the charges are of opposite signs).