Answer:
Velocity(v) = frequency(f) × wavelength
f = 0.3165
Wavelength = 2×length(L)
L = 157cm
Convert the length in centimetres to metre = 1.57m
v = 2×1.57 × 0.3165
v = 0.99m/s
Approx. 1m/s
Explanation:
The velocity of a wave is the product of its frequency and it's wavelength. The frequency is already known. The wavelength is the distance between two successive wave crests which is formed by sloshing water back and forth in the bath tub. Sloshing water to one end of the tub will produce a wave crest first at that end then the other completing a cycle. The wavelength will be twice the length of the bath tub as it is the distance that both crests are formed.
Wave crest is the highest point of a wave, and in this case is where the water rises to a high point in the bath tub
Answer:
The amount of work done required to stretch spring by additional 4 cm is 64 J.
Explanation:
The energy used for stretching spring is given by the relation :
.......(1)
Here k is spring constant and x is the displacement of spring from its equilibrium position.
For stretch spring by 2.0 cm or 0.02 m, we need 8.0 J of energy. Hence, substitute the suitable values in equation (1).
![8 = \frac{1}{2}\timesk\times k \times(0.02)^{2}](https://tex.z-dn.net/?f=8%20%3D%20%5Cfrac%7B1%7D%7B2%7D%5Ctimesk%5Ctimes%20k%20%5Ctimes%280.02%29%5E%7B2%7D)
k = 4 x 10⁴ N/m
Energy needed to stretch a spring by 6.0 cm can be determine by the equation (1).
Substitute 0.06 m for x and 4 x 10⁴ N/m for k in equation (1).
![E = \frac{1}{2}\times4\times10^{4}\times (0.06)^{2}](https://tex.z-dn.net/?f=E%20%3D%20%5Cfrac%7B1%7D%7B2%7D%5Ctimes4%5Ctimes10%5E%7B4%7D%5Ctimes%20%280.06%29%5E%7B2%7D)
E = 72 J
But we already have 8.0 J. So, the extra energy needed to stretch spring by additional 4 cm is :
E = ( 72 - 8 ) J = 64 J
Answer:
The pieces will attract one another
Explanation:
From the law of conservation of energy, we know that energy can neither be created nor destroyed, but transformed. If one piece of the toy that was neutral ends up having an electric charge (positive or negative), from the conservation of energy, the other piece must have a charge opposite to that on the other charged piece but equal in magnitude. These two pieces which are oppositely charged attracts each other, this shows that electric charge is conserved.
Answer:
![5.65487\times 10^{-8}\ Wb](https://tex.z-dn.net/?f=5.65487%5Ctimes%2010%5E%7B-8%7D%5C%20Wb)
![1.17\times 10^{-5}\ H](https://tex.z-dn.net/?f=1.17%5Ctimes%2010%5E%7B-5%7D%5C%20H)
-0.020475 V
Explanation:
= Vacuum permeability = ![4\pi \times 10^{-7}\ H/m](https://tex.z-dn.net/?f=4%5Cpi%20%5Ctimes%2010%5E%7B-7%7D%5C%20H%2Fm)
= Number of turns of coil = 25
= Number of turns of coil 2 = 300
= Rate of current increased = ![1.75\times 10^3\ A/s](https://tex.z-dn.net/?f=1.75%5Ctimes%2010%5E3%5C%20A%2Fs)
d = Diameter = 2 cm
r = Radius = ![\frac{d}{2}=\frac{2}{2}=1\ cm](https://tex.z-dn.net/?f=%5Cfrac%7Bd%7D%7B2%7D%3D%5Cfrac%7B2%7D%7B2%7D%3D1%5C%20cm)
A = Area = ![\pi r^2](https://tex.z-dn.net/?f=%5Cpi%20r%5E2)
Magnetic field in the solenoid is given by
![B=\mu_0\frac{N_2}{l}I\\\Rightarrow B=4\pi\times 10^{-7}\frac{300}{0.25}\times 0.12\\\Rightarrow B=0.00018\ T](https://tex.z-dn.net/?f=B%3D%5Cmu_0%5Cfrac%7BN_2%7D%7Bl%7DI%5C%5C%5CRightarrow%20B%3D4%5Cpi%5Ctimes%2010%5E%7B-7%7D%5Cfrac%7B300%7D%7B0.25%7D%5Ctimes%200.12%5C%5C%5CRightarrow%20B%3D0.00018%5C%20T)
Magnetic flux is given by
![\phi=BA\\\Rightarrow \phi=0.00018\times \pi\times 0.01^2\\\Rightarrow \phi=5.65487\times 10^{-8}\ Wb](https://tex.z-dn.net/?f=%5Cphi%3DBA%5C%5C%5CRightarrow%20%5Cphi%3D0.00018%5Ctimes%20%5Cpi%5Ctimes%200.01%5E2%5C%5C%5CRightarrow%20%5Cphi%3D5.65487%5Ctimes%2010%5E%7B-8%7D%5C%20Wb)
The average magnetic flux through each turn of the inner solenoid is
Mutual inductance is given by
![L=\frac{N_1\phi}{i_1}\\\Rightarrow L=\frac{25\times 5.65487\times 10^{-8}}{0.12}\\\Rightarrow L=1.17\times 10^{-5}\ H](https://tex.z-dn.net/?f=L%3D%5Cfrac%7BN_1%5Cphi%7D%7Bi_1%7D%5C%5C%5CRightarrow%20L%3D%5Cfrac%7B25%5Ctimes%205.65487%5Ctimes%2010%5E%7B-8%7D%7D%7B0.12%7D%5C%5C%5CRightarrow%20L%3D1.17%5Ctimes%2010%5E%7B-5%7D%5C%20H)
The mutual inductance of the two solenoids is ![1.17\times 10^{-5}\ H](https://tex.z-dn.net/?f=1.17%5Ctimes%2010%5E%7B-5%7D%5C%20H)
Induced emf is given by
![V=-L\frac{di_2}{dt}\\\Rightarrow V=-1.17\times 10^{-5}\times 1.75\times 10^3\\\Rightarrow V=-0.020475\ V](https://tex.z-dn.net/?f=V%3D-L%5Cfrac%7Bdi_2%7D%7Bdt%7D%5C%5C%5CRightarrow%20V%3D-1.17%5Ctimes%2010%5E%7B-5%7D%5Ctimes%201.75%5Ctimes%2010%5E3%5C%5C%5CRightarrow%20V%3D-0.020475%5C%20V)
The emf induced in the outer solenoid by the changing current in the inner solenoid is -0.020475 V