9.4 × 10⁻¹⁹ J. (2 sig. fig).
<h3>Explanation</h3>
The kinetic energy of an object depends on its mass and its speed. Mass is given for this neutron. However, the speed of the neutron needs to be found.
What's the speed of this neutron?
(3 sig. fig. Speed is an intermediate quantity. Include at least one more sig. fig. for the value of kinetic energy to be accurate to 2 sig. fig.)
What's the kinetic energy of this neutron?
,
where
is the mass of the object, and
is the speed of the object.
.
(2 sig. fig as in mass, distance travelled, and time).
On plato ;14.48 m/s
your welcome
Let us first calculate heat obtained by the evaporation of 51 g of water.
Given, heat of vaporization of water = 2.4 kJ/ g
∴ Heat obtained by evaporation of 51 g of water = 2.4 × 51 = 122.4 kJ
This is the heat energy available that can be used to cool water from 42°C to 20°C.
Specific heat of water is given by,
![C=\frac{Q}{mdt}](https://tex.z-dn.net/?f=%20C%3D%5Cfrac%7BQ%7D%7Bmdt%7D%20%20)
Here,
C is the specific heat of water = 4.18 J/gK
Q is the amount of heat = 122400 J
m is the mass of the water that can be cooled.
dt is the change in temperature= 42°C ₋ 20°C = 22°C ( The numerical value will be the same if Kelvin unit is used.)
Substituting the values we get,
![4.18=\frac{122400}{m*22}](https://tex.z-dn.net/?f=%204.18%3D%5Cfrac%7B122400%7D%7Bm%2A22%7D%20%20)
m = 1331 g
1331 grams of water can be cooled from 42°C to 20°C by evaporation of 51 g of water.
Answer:
A. investigates the overall structure and history of the Universe.
Explanation:
Astronomy is the branch of natural science that studies the objects of a celestial nature.
Cosmology is a part of astronomy that examines the origin and the how the universe changes with the passage of time. The model which is widely accepted as how the universe came into being is the Lambda-CDM model.
According to the Lambda-CDM model the universe consists of cold dark matter, matter and dark energy.