Answer:
Therefore,
The frequency heard by the engineer on train 1
Explanation:
Given:
Two trains on separate tracks move toward each other
For Train 1 Velocity of the observer,
For Train 2 Velocity of the Source,
Frequency of Source,
To Find:
Frequency of Observer,
(frequency heard by the engineer on train 1)
Solution:
Here we can use the Doppler effect equation to calculate both the velocity of the source 
and observer 
, the original frequency of the sound waves 
and the observed frequency of the sound waves 
,
The Equation is
Where,
v = velocity of sound in air = 343 m/s
Substituting the values we get
Therefore,
The frequency heard by the engineer on train 1
Answer:
299.88 kgm²/s
499.758 kgm²/s
Explanation:
R = Radius of merry-go-round = 1.63 m
I = Moment of inertia = 196 kgm²
= Initial angular velocity = 1.53 rad/s
m = Mass of person = 73 kg
v = Velocity = 4.2 m/s
Initial angular momentum is given by
The initial angular momentum of the merry-go-round is 299.88 kgm²/s
Angular momentum is given by
The angular momentum of the person 2 meters before she jumps on the merry-go-round is 499.758 kgm²/s
A) Vi= 60 m/s
a= -9.81 m/s^2
Vf= 0m/s^2
d=?
Vf^2=Vi^2+2ad
(0m/s)^2=(60m/s)^2+2(-9.81m/s^2)d
0=3600+(-19.62)d
-3600=(-19.62)d
(-3600)/(-19.62)=(-19.62)d/(-19.62)
d=183.5m
c) Vi= 60 m/s
a= -9.81 m/s^2
Vf= 0m/s^2
t=10s
d=?
d=Vi*t+(1/2)a*t^2
d=60m/s(10s)+(1/2)(-9.81m/s^2)(10s)^2
d=600+(-4.905)(100)
d=600+(-490.5)
d=108.5m
The answer is C) Surface runoff.
- Dmitri Mendeleev- arranged elements according to their
atomic mass
- Johann Wolfgang Dobereiner-created groups of three elements,
each based on similar properties
- John Newlands-used patterns to predict undiscovered
elements
- Antoine Lavoisier-divided elements into four categories
Explanation:
The periodic table or the table depicting the arrangement of various elements has a long history. Several of the scientist starting from Lavoisier to Mendeleev contributed to the table in their might. The present table has been an evolution of the previous tables over their shortcomings.
Some of the notable contributions include-
- Mendeleev- Mendeleev arranged the elements in order of atomic mass rather than atomic mass. Through this, he also discovered new elements.
- Newlands- He formulated the Newland law of octaves similar to musical notation.
- Lavoisier- Lavoisier divided the elements into various categories and also defined elements.
- Dobereiner- He formulated the triad law which encapsulated that certain group of elements showed similar properties, hence can be grouped together.
