14. The Aurora is an incredible light show caused by collisions between electrically charged particles released from the sun that enter the earth's atmosphere and collide with gases such as oxygen and nitrogen. The lights are seen around the magnetic poles of the northern and southern hemispheres.
15.
About 5.4 billion years from now, the sun will have exhausted all of its hydrogen. The sun's core will get really hot and dense, thus shrinking; however, the outer region of the sun will expand and grow. ... Even if the expanding dying sun doesn't reach Earth, the sun's high temperatures will completely burn the planet.
Answer:
Explanation:
Let's start by writing the equations of the forces along the two directions:
- Vertical:
where
N is the normal reaction
is the angle between the road and the horizontal
(mg) is the weight of the car, with m being its mass and g the acceleration of gravity
- Horizontal:
where
v is the speed of the car
r is the radius of the turn
Dividing the 2nd equation by the 1st one, we get:
In this problem:
(radius of the turn)
is the speed
Substituting, we find:
Answer:
The value is 
Explanation:
From the question we are told that
The radius of the inner conductor is 
The radius of the outer conductor is 
The potential at the outer conductor is 
Generally the capacitance per length of the capacitor like set up of the two conductors is
![C= \frac{2 * \pi * \epsilon_o }{ ln [\frac{r_2}{r_1} ]}](https://tex.z-dn.net/?f=C%3D%20%5Cfrac%7B2%20%2A%20%5Cpi%20%2A%20%5Cepsilon_o%20%7D%7B%20ln%20%5B%5Cfrac%7Br_2%7D%7Br_1%7D%20%5D%7D)
Here 
is the permitivity of free space with value 
=> ![C= \frac{2 * 3.142 * 8.85*10^{-12} }{ ln [\frac{0.003}{0.001} ]}](https://tex.z-dn.net/?f=C%3D%20%5Cfrac%7B2%20%2A%20%203.142%20%20%2A%208.85%2A10%5E%7B-12%7D%20%20%7D%7B%20ln%20%5B%5Cfrac%7B0.003%7D%7B0.001%7D%20%5D%7D)
=> 
Generally given that the potential of the outer conductor with respect to the inner conductor is positive it then mean that the outer conductor is positively charge
Generally the line charge density of the outer conductor is mathematically represented as
=> 
=> 
Generally the surface charge density is mathematically represented as
here 
=> 
=>
<span>Nuclear fission produces elements that are heavier than helium.
The elements that are used in nuclear fission and their products are much heavier than helium.</span>
Answer:
C. Surface area
Explanation:
The rate of chemical reaction depends on various factors such as:
- concentration and pressure
- nature of reactants
- temperature
- surface area
- presence of catalyst, etc.
Effect of surface area of reactants: the rate of a chemical reaction can be increased by increasing the the area of contact of the reacting substances. This is especially important when one or more of the reactants are solids., because only the particles of the solid that are exposed are able to take part in the reaction at each instant of time. Therefore, the greater the surface area of the solid reactant particles the faster the reaction.
The surface area of solid reactants can be increased by grinding or pelletizing, thus allowing for a greater contact between the reacting particles,
The instance in which one of the solid reactants was treated in a coffee grinder before adding to the reaction container is one way of increasing the surface area of a reactant.
