Answer:
Explanation:
Coulomb's law states that the force of attraction or repulsion between any two charges is proportional to the product of the magnitude of charges and inversely proportional to the square of the distance between the charges
⇒
∴
where 
is the force of attraction or repulsion
is Coulumb's constant=
and 
are the magnitude of the charges
is the distance between two charges
The force between the two charges is attractive if they are of different polarity
The force between the two charges is repulsive if they are of same polarity
Question 7:
Given: 
, 
By coulomb's law,
⇒
Question 6:
Given: 
, 
By coulomb's law,
⇒
Answer:
The speed and direction of the two players immediately after the tackle are 3.3 m/s and 53.4° South of West
Explanation:
given information:
mass of fullback, 
= 92 kg
speed of full back, 
= 5.8 to south
mass of lineman, 
=110 kg
speed of lineman, 
= 3.6
according to conservation energy,
assume that the collision is perfectly inelastic, thus
initial momentum = final momentum
= 
'
m₁v₁ = (m₁+m₂)'
' = m₁v₁/(m₁+m₂)
= (92) (5.8)/(92+110)
= 2.64 m/s
= 
'
m₂v₂ = (m₁+m₂)'
' = m₁v₁/(m₁+m₂)
= (110) (3.6)/(92+110)
= 1.96 m/s
thus,
' = √'²+'²
= 3.3 m/s
then, the direction of the two players is
θ = 90 - tan⁻¹('/')
= 90 - tan⁻¹(1.96/2.64)
= 53.4° South of West
Answer: Plastids are the site of manufacture and storage of important chemical compounds used by the cells of autotrophic eukaryotes
Explanation:
Thermos bottles are equipped with the parts that can prevent the hot water from cooling down by the three ways: Supporting the inner container by a few heat-insulating supporters to minimize the heat loss through heat conduction, using a vacuum space between the outer and the inner vessels to eliminate the heat loss by the air convection, and giving a high reflectivity to the inner surface of the outer vessel and the whole surface of the inner container to reduce the heat loss due to the radiation cooling.
