Answer:
Stars are at large distances that even light takes thousands of years to reach us from there.
for example, alpha centauri is 4300 light years away from earth and it is considered the nearest star to us, this means that light from there takes 4300 years to reach us and with a spaceships that can move with the speed of light is would take us 4300 years to get there which is imposible to live for that long.
hence, it is difficult to move between the stars.
Answer: The speed at the first quarter checkpoint is 0.74 m/s. The speed at the second quarter checkpoint is 1.40 m/s. The speed at the third quarter checkpoint is 1.61 m/s. The speed at the finish line is 1.89 m/s.
Explanation: I did the assignment and got it correct :)
(6) first choice: the frequency appears higher and wavelength is shorter.
The car approaches a stationary observer and so the sound will appear to have shorter wavelength. This creates an effect of its siren to sound with higher frequency than it would do if both were stationary.
(7) The Doppler formula for frequency in the case of a stationary observer and source approaching it is as follows:
The wavelength is then
The third choice "0.80m; 431Hz" is correct
1. HP is the output horsepower rating of an engine, while Brake horse power is the input brake horsepower of an engine. ... Brake horse power is the measurement of an engine's power without any power losses, while HP is less the power losses Brake horse power
Answer:
the final kinetic energy is 0.9eV
Explanation:
To find the kinetic energy of the electron just after the collision with hydrogen atoms you take into account that the energy of the electron in the hydrogen atoms are given by the expression:
you can assume that the shot electron excites the electron of the hydrogen atom to the first excited state, that is
-10.2eV is the energy that the shot electron losses in the excitation of the electron of the hydrogen atom. Hence, the final kinetic energy of the shot electron after it has given -10.2eV of its energy is: