Answer:
120 m
Explanation:
Given:
wavelength 'λ' = 2.4m
pulse width 'τ'= 100T ('T' is the time of one oscillation)
The below inequality express the range of distances to an object that radar can detect
τc/2 < x < Tc/2 ---->eq(1)
Where, τc/2 is the shortest distance
First we'll calculate Frequency 'f' in order to determine time of one oscillation 'T'
f = c/λ (c= speed of light i.e 3 x
m/s)
f= 3 x
/ 2.4
f=1.25 x
hz.
As, T= 1/f
time of one oscillation T= 1/1.25 x
T= 8 x
s
It was given that pulse width 'τ'= 100T
τ= 100 x 8 x
=> 800 x
s
From eq(1), we can conclude that the shortest distance to an object that this radar can detect:
= τc/2 => (800 x
x 3 x
)/2
=120m
Displacement can be zero so velocity is zero but the distance won’t be zero so speed won’t be zero
Answer:
<em>The volume of the feathers in ft³ = 16 ft³</em>
Explanation:
Density: This can be defined as the ratio of mass of a body to the corresponding volume of that body. The S.I unit of Density is kg/m³
Mathematically it can be expressed as,
D = m/v ................................... Equation 1
making v the subject of the equation above,
v = m/D ............................. Equation 2
Where D = Density of the feathers, m = mass of the feathers, v = volume of the feathers.
Given: D = 0.50 lbs/ft³, m = 8.0 lbs.
Substituting into equation 2
v = 8/0.5
v = 16 ft³
<em>Thus the volume of the feathers in ft³ = 16 ft³</em>
An electron in the Bohr model of hydrogen revolves around the nucleus to possess energy.
Answer: Option B
<u>Explanation:</u>
According to Rutherford, it was stated that electrons are the subatomic particles which revolve around the nucleus. But the error of spiral collapse of these electrons is due to absence of electrons in discrete levels. Hence, in Bohr atom model, the atom's negative or electrons are said to rotate in respective energy levels.
So, they keep on revolving around a nucleus in Bohr atom is said to revolve around a nucleus in order to possess energy. Thus, each level will exhibit discrete energy levels which will contain electrons of specific energy only.
Answer:

Explanation:
The force of drag is given by

C is coefficient of drag
is density of air
A is area which is given by 
V is the velocity
