Answer:
1) t=1.743 sec
2)Vo=61.388 m/sec
3)the x component of its velocity just be- fore it strikes the ground is the same as the initial velocity of the ball that is=61.388 m/sec
4)Vf=17.08 m/s
Explanation:
1)From second equation of motion we get
h=Vit+(1/2)gt^2
here in case(a): Vi=0 m/s,h=14.9m,,put these values in above equation to find the time the ball is in motion
14.9=(0)*t+(1/2)(9.8)t^2
t^2=14.9/4.9
t^2=3.040 sec
t=1.743 sec
2) s=Vo*t
Putting values we get
107=Vo*1.743
Vo=61.388 m/sec
3)the x component of its velocity just be- fore it strikes the ground is the same as the initial velocity of the ball that is=61.388 m/sec
4)From third equation of motion we know that
Vf^2-Vi^2=2gh
here Vi=0 m/s,h=14.9 m
Vf^2=Vi^2+2gh=0+2(9.8)(14.9)
Vf^2=292.04
Vf=17.08 m/s
The age of the galaxy when we look back is 13.97 billion years.
The given parameters:
- <em>distance of the galaxy, x = 2,000 Mpc</em>
According Hubble's law the age of the universe is calculated as follows;
v = H₀x
where;
H₀ = 70 km/s/Mpc

Thus, the age of the galaxy when we look back is 13.97 billion years.
Learn more about Hubble's law here: brainly.com/question/19819028
Answer:
a) 
b) 
c) 
d) 
Explanation:
<u>Given equation of pressure variation:</u>
![\Delta P= (1.78\ Pa)\ sin\ [(0.888\ m^{-1})x-(500\ s^{-1})t]](https://tex.z-dn.net/?f=%5CDelta%20P%3D%20%281.78%5C%20Pa%29%5C%20sin%5C%20%5B%280.888%5C%20m%5E%7B-1%7D%29x-%28500%5C%20s%5E%7B-1%7D%29t%5D)
We have the standard equation of periodic oscillations:

<em>By comparing, we deduce:</em>
(a)
amplitude:

(b)
angular frequency:


∴Frequency of oscillations:


(c)
wavelength is given by:



(d)
Speed of the wave is gives by:



Answer:

Explanation:
According to Coulomb's law, the magnitude of the electric force between two point charges is directly proportional to the product of the magnitude of both charges and inversely proportional to the square of the distance that separates them:

Here k is the Coulomb constant. In this case, we have
,
and
. Replacing the values:

The negative sign indicates that it is an attractive force. So, the magnitude of the electric force is:
