Answer:
![v_0=9.9\ m.s^{-1}](https://tex.z-dn.net/?f=v_0%3D9.9%5C%20m.s%5E%7B-1%7D)
Explanation:
Given:
- angle of launch of projectile from horizontal,
![\theta=15^{\circ}](https://tex.z-dn.net/?f=%5Ctheta%3D15%5E%7B%5Ccirc%7D)
- range of projectile,
![R=5\ m](https://tex.z-dn.net/?f=R%3D5%5C%20m)
<u>We have formula for the range of projectile:</u>
![R=\frac{v_0^2\times sin\ 2\theta}{g}](https://tex.z-dn.net/?f=R%3D%5Cfrac%7Bv_0%5E2%5Ctimes%20sin%5C%202%5Ctheta%7D%7Bg%7D)
putting the respective values
![5=\frac{v_0^2\times sin\ 30^{\circ}}{9.8}](https://tex.z-dn.net/?f=5%3D%5Cfrac%7Bv_0%5E2%5Ctimes%20sin%5C%2030%5E%7B%5Ccirc%7D%7D%7B9.8%7D)
is the velocity with which Tom should jump to land on the other roof.
Answer:
1. They should not trust this study. 2. Pseudoscience.
Explanation:
Because they drank the water and after 24 hours, they said that it was gone. Head aches go away sooner than that. Another reason is that some people could have lied about having a headache just so they could have the water or their headache could have gone away before they drank the water.
Answer:
+5.4×10⁻⁷ C
Explanation:
Electric potential: This can be defined as the work done in bringing a unit charge from infinity to that point against the action of the field. The S.I unit of potential is volt (V)
The formula for potential is
V = kq/r............................ Equation 1
Where V = electric potential, k = proportionality constant, q = charge, r = distance.
making q the subject of the equation,
q = Vr/k............................ Equation 2
Given: V = 490 V, r = 10 m,
Constant: k = 9×10⁹ Nm²/C²
Substitute into equation 2
q = 490(10)/(9×10⁹)
q = 5.4×10⁻⁷ C
q = +5.4×10⁻⁷ C
Hence the charge is +5.4×10⁻⁷ C
Answer:
First, as you may know, the light travels at a given velocity.
In vaccum, this velocity is c = 3x10^8 m/s.
And we know that:
distance = velocity*time
Now, if some object (like a star ) is really far away, the light that comes from that star may take years to reach the Earth.
This means that the images that the astronomers see today, actually happened years and years ago (So the night sky is like a picture of the "past" of the universe)
Also, for example, if an astronomer sees some particular thing, he can apply a model (a "simplification" of some phenomena that is used to simplify it an explain it) and with the model, the scientist can infer the information of the given thing some time before it was seen.
Explanation:
Attachments of the solution are below.