Density= how much mass is in a certain volume
Therefore, you do (mass/volume).
density of the block is
36g/9cm3
or
4g/cm3
Meaning that there is 4 grams of mass in each cm3.
Answer:
Option B
Explanation:
Magnification of Microscope is

Mo= Magnification of objective lens and
Me= magnification of the eyepiece.
Both magnifications( of objective and eyepiece) are inversely proportional to the focal length.
Magnification,

when the focal length is less magnification will be high and when the magnification is the low focal length of the microscope will be more.
Thus. Magnification will increase by decreasing the focal length.
The correct answer is Option B i.e. using shorter focal length
Answer:
The frequency of infrared wave is 35.385 GHz
Explanation:
Given data:
Wavelength of infrared light = 8.45 mm = 8.45 x
m
Velocity of infrared light = 2.99 x
m/s
To find: frequency of the infrared wave = ?
We know that the wavelength and frequency are inversely proportional and the formula to derive frequency with velocity and wavelength is:
c = μλ, where
c is velocity of light
μ is frequency of light
λ is wavelength of light
Hence the frequency of light μ = c/λ
= 
=
x

= 35.385 x
Hz (since 1
= 1 Hz)
= 35.385 GHz
Answer:
a) v2=4147.72 m/s
b) stotal=5.53x10^6 m
Explanation:
a) the length from the center of the earth is equal to:
L1=1x10^6+((6.37/2)x10^6)=4.18x10^6 m
the velocity is 5.14 km/s=5.14x10^3 m/s
the farthest distance is equal to:
L2=2x10^6+((6.37/2)x10^6)=5.18x10^6 m
As the angular momentum is conserved, we have to:
I1=I2
m*L1*v1=m*L2*V2, where m is the mass of satelite
clearing v2:
v2=(L1*V1)/L2=(4.18x10^6*5.14x10^3)/5.18x10^6=4147.72 m/s
b) Using the Newton 3rd law:
vf^2=vi^2+2as
where:
a=g=9.8 m/s^2
vf=0
vi=5.14 km/s
s=?
Clearing s:
s=(vf^2-vi^2)/(2g)=((0-(5.14x10^3)^2)/(2*9.8)=1.35x10^6 m
the total distance is equal to:
stotal=s+L1=1.35x10^6+4.18x10^6=5.53x10^6 m
Answer:
Explanation:
Given
Child falls a height of 
Applying conservation of energy we can write
Loss in Potential energy=Gain in kinetic energy





Thus child reaches a velocity of 4.42 m/s