Answer:
(A.)Nuclear fission and beta decay (electron emission)
Answer:
Explanation:
A mass of 700 kg will exert a force of
700 x 9.8
= 6860 N.
Amount of compression x = 4 cm
= 4 x 10⁻² m
Force constant K = force of compression / compression
= 6860 / 4 x 10⁻²
= 1715 x 10² Nm⁻¹.
Let us take compression of r at any moment
Restoring force by spring
= k r
Force required to compress = kr
Let it is compressed by small length dr during which force will remain constant.
Work done
dW = Force x displacement
= -kr -dr
= kr dr
Work done to compress by length d
for it r ranges from 0 to -d
Integrating on both sides
W = 
= [ kr²/2]₀^-4
= 1/2 kX16X10⁻⁴
= .5 x 1715 x 10² x 16 x 10⁻⁴
= 137.20 J
Answer:
When iron rusts - in the presence of moisture and oxygen - iron-oxide is formed. Iron oxide is nothing but a compound of iron and oxygen. There is an increase in the mass of the iron equal to the mass of oxygen that has gone into forming the rust.
<em>hope it helps:)</em>
You force air from your lungs up through your larynx which is commonly called the voicebox