Answer:
2.89 hours
Explanation:
given :
Vo = 72 km/h
Vt = 90 km/h
S = 234 km
find : the time taken (t) = ?
solution :
2.a.s = Vt² - Vo²
2.a.(234) = 90²- 72²
468.a = 8100 - 5184
= 2916
a = 2916/468 = 6.23 km/h²
so,
t = (Vt-Vo) /a
= (90-72)/ 6.23
= 18/ 6.23
= 2.89 hours
Answer:
V = 493421.05 [gal]
Explanation:
This is a problem that consists of handling units, we can calculate by first-hand the volume, then convert units from cubic meters to gallons.
V = 50 * 25 * 1.5
V = 1875 [m^3]
Now we need to convert units, using the proper conversion factor.
![1875[m^3]*\frac{1000lt}{1m^3} *\frac{1gal}{3.8lt} \\493421.05[gal]](https://tex.z-dn.net/?f=1875%5Bm%5E3%5D%2A%5Cfrac%7B1000lt%7D%7B1m%5E3%7D%20%2A%5Cfrac%7B1gal%7D%7B3.8lt%7D%20%5C%5C493421.05%5Bgal%5D)
According to the information provided to define an average density, it is necessary to use the concepts related to mass calculation based on gravitational constants and radius, as well as the calculation of the volume of a sphere.
By definition we know that the mass of a body in this case of the earth is given as a function of

Where,
g= gravitational acceleration
G = Universal gravitational constant
r = radius (earth at this case)
All of this values we have,

Replacing at this equation we have that

The Volume of a Sphere is equal to

Therefore using the relation between mass, volume and density we have that

Answer:
The diameter of the moon's image is 0.31 cm.
Explanation:
Given that,
Focal length = 34.3 cm
Diameter of the moon 
Mean distance from the earth 
At that distance the object is assumes to be at infinity. hence the image will be formed at a distance equal to focal length
So, the image distance is 34.3 cm.
We need to calculate the diameter of the moon's image
Using formula of magnification




Hence, The diameter of the moon's image is 0.31 cm.