Answer:
What material structure explanation lies behind the fact that the propagation velocity of longitudinal waves is the lowest in gases and the highest in solids?
<span>Both electric and magnetic fields exert body forces, meaning they act from a distance. The like charges and poles in both repel; positive charge repels positive and the north pole repels the north pole. For both, the opposite poles/charges attract. Finally, only magnetic fields have poles, and there are two poles, namely the south and north, so they are dipolar.
The diagram that represents all of this information correctly is the third.</span>
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:20°
Explanation:
Recall
Range R of a projectile is given by U^2sin2A/g
We're U = velocity,A= angle of projection and g is acceleration due to gravity
From the question the range R are the same
Hence R1=R2
U1^2sin2A/g=U2^2sin2B/g
But U1=U2 and g=g
Hence sin2A=sin 2B
Sin 2*70= sin2*B
0.6427=sin2B
B=sin inverse(0.6427)=40/2=20°
So, using the periodic table of elements, we know that the atomic number of sulfur is 16, which stands for the number of protons/electrons in the atom. Since the mass number, in this case is 34, is the sum of protons and neutrons, all we have to do is subtract 16 from 34, which will give us 18, the number of neutrons for this isotope of sulfur. :)
