Answer:
The time taken to reach the maximum height is 3.20 seconds
Explanation:
The given parameters are;
The initial height from which the volcano erupts the lava bomb = 64.4 m
The initial upward velocity of the lava bomb = 31.4 m/s
The acceleration due to gravity, g = 9.8 m/s²
The time it takes the lava bomb to reach its maximum height, t, is given by the following kinematic equation as follows;
v = u - g·t
Where;
v = The final velocity = 0 m/s at maximum height
u = The initial velocity = 31.4 m/s
g = The acceleration due to gravity = 9.8 m/s²
t = The time taken to reach the maximum height
Substituting the values gives;
0 = 31.4 - 9.8 × t
∴ 31.4 = 9.8 × t
t = 31.4/9.8 ≈ 3.204
The time taken to reach the maximum height rounded to three significant figures = t ≈ 3.20 seconds
Out of the choices given, the statement about how light travels is "<span>Light can travel in a vacuum, and it travels faster if the light source is moving."</span>
At the present time, the only way we know of that light can get shifted
toward the blue end of the spectrum is the Doppler effect ... wavelengths
appear shorter than they should be when the source is moving toward us.
IF that's true in the case of the Andromeda galaxy, it means the galaxy is
moving toward us.
We use the same reasoning to conclude that all the galaxies whose light is red-shifted are moving away from us. That includes the vast majority of all galaxies that we can see, and it strongly supports the theory of the big bang
and the expanding universe.
If somebody ever comes along and discovers a DIFFERENT way that light
can get shifted to new, longer or shorter wavelengths, then pretty much all
of modern Cosmology will be out the window. There's a lot riding on the
Doppler effect !
Here we can use coulomb's law to find the force between two charges
As per coulombs law
]tex]F = \frac{kq_1q_2}{r^2}[/tex]
here we have
now by using the above equation we have
so here the force between two charges is of above magnitude and this will be repulsive force between them as both charges are of same sign.
Answer:
As we are converting 220V AC into a 5V DC, first we need a step-down transformer to reduce such high voltage. Here we have used 9-0-9 1A step-down transformer, which convert 220V AC to 9V AC. In transformer there are primary and secondary coils which step up or step down the voltage according to the no of turn in the coils.
Selection of proper transformer is very important. Current rating depends upon the Current requirement of Load circuit (circuit which will use the generate DC). The voltage rating should be more than the required voltage. Means if we need 5V DC, transformer should at least have a rating of 7V, because voltage regulator IC 7805 at least need 2V more i.e. 7V to provide a 5V voltage.
