Answer:
when you are pushing the pedal you are causing the pedal to move done and then you will move 100cm
Explanation:
10 cm= 100 cm moved so when you move you will move because you are timeing the 10 by 100 to get the spped
Answer:
the correct one is D,
Ultraviolet, x-ray, gamma ray
Explanation:
Electromagnetism radiation are waves of energy that is expressed by the Planck relationship
E = h f
where h is the plank constant and f the frequency of the radiation.
Also the speed of light is
c = λ f
we substitute
E = h c /λ
therefore to damage the cells of the body radiation of appreciable energy is needed
microwave radiation has an energy of 10⁻⁵ eV
infrared radiation E = 10⁻² eV
visible radiation E = 1 to 3 eV
radiation Uv E = 3 to 6 eV
X-ray E = 10 eV
gamma rays E = 10 5 eV
therefore we see that the high energy radiation is gamma rays, x-rays and ultraviolet light.
When checking the answers, the correct one is D
Answer:
DS = 13865.7[J/K]
Explanation:
We can calculate the energy of the rock, like the potential energy relative to the lake level. Which can be calculated by means of the following expression of the potential energy:
![E_{p}=m*g*h\\\\where:\\m = mass = 2000[kg]\\h = elevation = 200 [m]\\g = gravity = 9.81[m/s^2]](https://tex.z-dn.net/?f=E_%7Bp%7D%3Dm%2Ag%2Ah%5C%5C%5C%5Cwhere%3A%5C%5Cm%20%3D%20mass%20%3D%202000%5Bkg%5D%5C%5Ch%20%3D%20elevation%20%3D%20200%20%5Bm%5D%5C%5Cg%20%3D%20gravity%20%3D%209.81%5Bm%2Fs%5E2%5D)
Therefore:
![E_{p}=2000*9.81*200\\E_{p}=3924000 [J]\\](https://tex.z-dn.net/?f=E_%7Bp%7D%3D2000%2A9.81%2A200%5C%5CE_%7Bp%7D%3D3924000%20%5BJ%5D%5C%5C)
This energy is transformed into thermal energy.
we shall remember that isothermal heat transfer processes are internally reversible, so the entropy change of a system during one of these processes can be determined, by the following expression.
![DS=\frac{Q}{T}\\ where:\\DS = entropy change [J/K]\\Q = Heat transfer [J]\\T = temperature [K]](https://tex.z-dn.net/?f=DS%3D%5Cfrac%7BQ%7D%7BT%7D%5C%5C%20where%3A%5C%5CDS%20%3D%20entropy%20change%20%5BJ%2FK%5D%5C%5CQ%20%3D%20Heat%20transfer%20%5BJ%5D%5C%5CT%20%3D%20temperature%20%5BK%5D)
T = 5 + 278 = 283[K]
DS = 3924000 / 283
DS = 13865.7[J/K]
Answer:
Explanation:
The work required to push will be equal to work done by friction . Let d be the displacement required .
force of friction = mg x μ where m is mass of the suitcase , μ be the coefficient of friction
work done by force of friction
mg x μ x d = 660
80 x 9.8 x .272 x d = 660
d = 3 .1 m .
