Answer:
(a) 
(b) 
Explanation:
(a) We use Newton's law of universal gravitation, in order to calculate the gravitational force between electron and proton:
Where G is the Cavendish gravitational constant, 
and 
are the masses of the electron and the proton respectively and r is the distance between them:
The minus sing indicates that the force is repulsive. Thus, its magnitude is:
(b) We use Coulomb's law, in order to calculate the electric force between electron and proton, here k is the Coulomb constant and e is the elementary charge:
Its magnitude is:
Answer:
This is due to bending of light ray passing through the medium.
Explanation:
This can be explained using the concept of refraction.
Refraction can be defined as the bending of light ray as it travels from one medium to another (it can be from the less dense to denser medium or denser to less dense medium)
For that of pencil in water, light ray travels from less dense medium(surrounding air) to denser medium(water). This causes the pencil to bend away from the normal rather than towards the normal (angle of refraction being greater than angle of incidence) and hence the reason for the bending.
NB: Normal line is perpendicular to the plane between the medium.
Answer:
density = 0.0933 kg/m
speed = 27.581 m/s
Explanation:
given data
length L = 4.5 m
mass m = 0.42 kg
force F = 71 N
to find out
mass density and speed
solution
we find linear mass density
linear mass density = mass / length
put here all value
density = 0.42 / 4.5
density = 0.0933 kg/m
and
speed of wave
speed = √(F/density)
speed = √(0.42/0.933)
speed = 27.581 m/s
Answer:
Victor will always be able to select 4 of those cards with the following property
Explanation:
Number of trading cards = 100
victor selects 21 cards
let the 4 cards be labelled : A,B,C and D
The average power level of : A,B,C,D = ( A + B + C + D )/ 4 = P
let the two pairs be : ( A + B ) and ( C + D )
note: average power of each pair = P and this shows that
( A + B ) = ( C + D ) for Victor to select 4 cards out of the 21 cards that exhibit the same property
we have to check out the possible choices of two cards out of 21 cards yield distinct sums.
= C(21,2)=(21x20)/2 = 210.
from the question the number of distinct sums that can be created using 101 through 200 is < 210 .
hence it is impossible to get 210 distinct sums therefore Victor will always be able to select 4 of those cards
Yes, I do! Vectors have a direction linked to them and scalars don’t.
