Given that metal cases of electrical appliances are connected to the wire, let's select the statement which is not correct from the list of statements.
The earth wire is used to protect you and help reduce the risk of receiving an electric shock. The earth wire reduces the risk of electric shock by creating a path for a fault or lose current to flow to the Earth.
The Live wire may become loose and touch the metal case. In this case, the earth wire will channel the fault current to the earth thereby reducing the risk of electric shock.
If the metal case becomes live, the earth wire conducts current to the ground. This helps prevent electric shock from the metal case.
The Earth wire has low or no resistance. It is always made of copper.
It provides a low resistance path to the ground.
Therefore, the statement ''the earth wire needs to have high resistance'' is NOT current.
ANSWER:
C. The earth wire needs to have a high reistance.
Kepler derived his three laws of planetary motion entirely from
observations of the planets and their motions in the sky.
Newton published his law of universal gravitation almost a hundred
years later. Using some calculus and some analytic geometry, which
any serious sophomore in an engineering college should be able to do,
it can be shown that IF Newton's law of gravitation is correct, then it MUST
lead to Kepler's laws. Gravity, as Newton described it, must make the planets
in their orbits behave exactly as they do.
This demonstration is a tremendous boost for the work of both Kepler
and Newton.
Answer:3.87*10^-4
Explanation:
What is the decrease in mass, delta mass Xe , of the xenon nucleus as a result of this deca
We have been given the wavelength of the gamma ray, find the frequency using c = freq*wavelength.
C=f*lambda
3*10^8=f*3.44*10^-12
F=0.87*10^20 hz
Then with the frequency, find the energy emitted using equation
E=hf E = freq*Plank's constant
E=.87*10^20*6.62*10^-34
E=575.94*10^(-16)
With this energy, convert into MeV from joules.
With the energy in MeV, use E=mc^2 using c^2 = 931.5 MeV/u.
Plugging and computing all necessary numbers gives you
3.87*10^-4 u.
Answer:
b) 252 Hz or 260 Hz
c) 0.25 s
Explanation:
b) The frequency of the beats is 4 Hz, and one tuning fork has a frequency of 256 Hz. Therefore, the second tuning fork is either 4 Hz lower or 4 Hz higher.
f = 252 Hz or 260 Hz
c) Period is the inverse of frequency.
T = 1/f
T = 1 / (4 Hz)
T = 0.25 s