Kepler's second law of planetary motion<span> describes the speed of a </span>planet<span> traveling in an elliptical orbit around the sun. It states that a line between the sun and the </span>planetsweeps equal areas in equal times. Thus, the speed of theplanet<span> increases as it nears the sun and decreases as it recedes from the sun.</span>
Answer:
a) 
, b) 
, c) 
Explanation:
a) The change in the gravitational potential energy of the marble-Earth system is:
b) The change in the elastic potential energy of the spring is equal to the change in the gravitational potential energy, then:
c) The spring constant of the gun is:
Answer: 
Explanation:
Acceleration 
is expressed in the following formula:
Where:
is the final velocity of the projectile
is the initial velocity of the projectile
is the time
Solving:
This is the acceleration of the projectile
Answer:
2. Wavelength
Explanation:
When a photon collides with an electron and is deflected, the photon’s wavelength decreases.
When photon gained energy by the collision of the electron. Its energy and frequency will be increased and its wavelength will be decreased.
