Answer:
0.002925 m
Explanation:
Lt = LO(1 +α Δt ) here Lt is total length Lo is original length α is coefficient of linear expansion and Δt is change in temperature
<h2>for aluminium</h2>
α=25×10^-6
Lt = 5(1+25×10^-6×(70-20))
Lt = 5 (1+25×10^-6×50)
Lt = 5 ( 1+0.00125)
Lt = 5×1.00125
Lt =5.00625 m
<h2>for nickel </h2>
α=13.3×10^-6
Lt =5(1+13.3×10^-6×50)
Lt = 5(1+0.000665)
Lt =5.003325 m
hence difference in length =5.00625-5.003325
= 0.002925 m
Answer:
The elastic potential energy is zero.
The net force acting on the spring is zero.
Explanation:
The equilibrium position of a spring is the position that the spring has when its neither compressed nor stretched - it is also called natural length of the spring.
Let's now analyze the different statements:
The spring constant is zero. --> false. The spring constant is never zero.
The elastic potential energy is at a maximum --> false. The elastic potential energy of a spring is given by

where k is the spring constant and x the displacement. Therefore, the elastic potential energy is maximum when x, the displacement, is maximum.
The elastic potential energy is zero. --> true. As we saw from the equation above, the elastic potential energy is zero when the displacement is zero (at the equilibrium position).
The displacement of the spring is at a maxi
num --> false, for what we said above
The net force acting on the spring is zero. --> true, as the spring is neither compressed nor stretched
Answer:
halved
Explanation:
The velocity of the a wave is obtained by multiplying the frequency and wavelength.

Where
v = Velocity
f = Frequency
= Wavelength
The velocity here is constant. So, if the frequency is doubled the wavelength is halved.
Magnetic flux can be calculated by the product of the magnetic field and the area that is perpendicular to the field that it penetrates. It has units of Weber or Tesla-m^2. For the first question, when there is no current in the coil, the flux would be:
ΦB = BA
A = πr^2
A = π(.1 m)^2
A = π/100 m^2
ΦB = 2.60x10^-3 T (π/100 m^2 ) ΦB = 8.17x10^-5 T-m^2 or Wb (This is only for one loop of the coil)
The inductance on the coil given the current flows in a certain direction can be calculated by the product of the total number of turns in the coil and the flux of one loop over the current passing through. We do as follows:
L = N (ΦB ) / I
L = 30 (8.17x10^-5 T-m^2) / 3.80 = 6.44x10^-4 mH
It is required an infinite work. The additional electron will never reach the origin.
In fact, assuming the additional electron is coming from the positive direction, as it approaches x=+1.00 m it will become closer and closer to the electron located at x=+1.00 m. However, the electrostatic force between the two electrons (which is repulsive) will become infinite when the second electron reaches x=+1.00 m, because the distance d between the two electrons is zero:

So, in order for the additional electron to cross this point, it is required an infinite amount of work, which is impossible.