Answer:
Explanation:
energy stored in spring initially
= kinetic + potential energy of block + energy dissipated by friction
= 1/2 mv² + mgh + μ mgcosθ x d
m is mass , v is velocity at top position , h is vertical height , μ is coefficient of friction ,θ is angle of inclination of plane
= m (1/2 v² + gh + μ gcosθ x d )
= 1.05 ( .5 x 5.1² + 9.8 x 4.9 sin35 + .55 x 9.8 cos35 x 4.9 )
= 1.05 ( 13.005 + 27.543 + 21.635)
= 65.3 J .
Answer:
the force of attraction between the two charges is 4.2 x 10⁹ N.
Explanation:
Given;
the magnitude of first charge, q₁ = 0.06 C
the magnitude of the second charge, q₂ = 0.07 C
distance between the two charges, r = 3 m
The force of attraction between the two charges is calculated as ;
where;
k is Coulomb's constant = 9 x 10⁹ Nm²/C²
Therefore, the force of attraction between the two charges is 4.2 x 10⁹ N.
The Doppler effect happens as the result of a source of waves having relative motion to observers somewhere else consider that if something is producing a wave of wavelength W and it is moving relative to the waves then as the waves spread out it seems to chase one side and run away from the other side there for wavelengths produced on the scale it is chasing will be less than W on the side it is running away from the apparent wavelength will be greater than W so using this knowledge if the source of the Waves moves faster than it will chase one of the more closely and run away from the other more quickly there for making the short wavelength even shorter and the long wavelength even longer can turn you in and tell you have gone all over the speed of wave creating boom when dealing with sound this is what causes a sonic boom this lengthening of the long wavelengths and the shortening of the short wavelengths is referred to as being a greater Doppler shift
Answer:
False
Explanation:
According to the big bang theory, matter was an infinitely small and very high density point which at one point exploded and expanded in all directions, creating what we know as our Universe, which also includes space and time . This happened about 13.8 billion years ago. Theoretical physicists have managed to reconstruct this chronology of events from 1/100 of a second after the Big Bang. After the explosion, while the Universe expanded, it cooled sufficiently and the first subatomic particles were formed: Electrons, Positrons, Mesons, Barions, Neutrinos, Photons among others. Today more than 90 particles are known. This theory solves many unknowns and is very well received by the scientific community, however there is still much to solve, for example, one of the great unsolved scientific problems in the expanding Universe model is whether the Universe is open or closed.
An attempt to solve this problem is to determine if the average density of matter in the Universe is greater than the critical value in Friedmann's model. The mass of a galaxy can be measured by observing the movement of its stars; multiplying the mass of each galaxy by the number of galaxies, it is seen that the density is only 5 to 10% of the critical value.
Supposedly there is life on Mars but it’s early to say for sure
