Answers:
a) 
b) 
c) 
d) 
Explanation:
For this situation we will use the following equations:
(1)
(2)
Where:
is the <u>height of the model rocket at a given time</u>
is the i<u>nitial height </u>of the model rocket
is the<u> initial velocity</u> of the model rocket since it started from rest
is the <u>velocity of the rocket at a given height and time</u>
is the <u>time</u> it takes to the model rocket to reach a certain height
is the <u>constant acceleration</u> due gravity and the rocket's thrust
<h2>a) Time it takes for the rocket to reach the height=4.2 m</h2>
The average velocity of a body moving at a constant acceleration is:
(3)
For this rocket is:
(4)
Time is determined by:
(5)
(6)
Hence:
(7)
<h2>b) Magnitude of the rocket's acceleration</h2>
Using equation (1), with initial height and velocity equal to zero:
(8)
We will use 
:
(9)
Finding :
(10)
<h2>c) Height of the rocket 0.20 s after launch</h2>
Using again but for 
:
(11)
(12)
<h2>d) Speed of the rocket 0.20 s after launch</h2>
We will use equation (2) remembering the rocket startted from rest:
(13)
(14)
Finally:
(15)
Energy can only be converted from one form to another
eg kinetic energy is converted to heat energy
The following lists of
stars in order from least density to greatest density are giant, main sequence
star, white dwarf, neutron star. The answer is letter B. Aside from neutron
star being the densest star, it is also the smallest star compared to the giant
star, as its name implied.
Correct answer choice is :
A) As speed changes, wavelength changes and frequency remains constant.
Explanation:
The higher the energy, the higher the frequency and the smaller the wavelength. The relation among wavelength and frequency the greater the frequency, the smaller the wavelength it reflects that short wavelengths are more dynamic than large wavelengths. The wavelength and frequency of light are almost associated. The greater the frequency, the smaller the wavelength. Because all small waves move into space at the very speed, the amount of wave peaks spending by a read point in one second depends on the wavelength.
