The answer is 60 km. I hope it helps i dont know if this is right or wrong.
Answer:
Total momentum = 16 Kgm/s
Explanation:
Let the momentum of the two balls be A and B respectively.
Momentum A = 16 kgm/s
Momentum B = 0 kgm/s (since the ball is at rest).
Total momentum = A + B
Total momentum = 16 + 0
Total momentum = 16 Kgm/s
Momentum can be defined as the multiplication (product) of the mass possessed by an object and its velocity. Momentum is considered to be a vector quantity because it has both magnitude and direction.
Mathematically, momentum is given by the formula;
The terms are both about changing states. Vaporizing is when you heat something up into a vapor; condensation is when you lower a vapors temperature to make it become a liquid state.
Answer:
red shift, indicating that the universe is expanding
Explanation:
Doppler effect occurs when a source of a wave (e.g. light, or sound waves) moves relative to an observer; as a result of this relative motion, the wavelength of the wave appears lengthened/shortened to the observer. Two situations can occur:
- The source of the wave is moving towards the observer - in this case, the wavelength of the wave becomes shorter. If the wave is visible light, such as the light emitted by distant galaxies, this means that the wavelength of the light shifts towards the blue-end of the spectrum (blue-shift)
- The source of the wave is moving away from the observer - in this case, the wavelength of the wave becomes longer. If the wave is visible light, such as the light emitted by distant galaxies, this means that the wavelength of the light shifts towards the red-end of the spectrum (red-shift)
In our universe, we observe a red-shift for all the distant galaxies: this means that these galaxies are moving away from us, so this is an indication that the universe is expanding.
Gravity
The moon doesn't smash into the earth because the gravity from the earth keeps the moon in orbit around it.
