Explanation:
Gravitational potential energy = mgh = (5)(9.81)(7) = 343.35J.
Heat required to raise the temperature of a given system is

here we know that
m = mass
s = specific heat capacity
= change in temperature
now as we know that
mass of wood = 5 kg
mass of aluminium pan = 2 kg
change in temperature = 45 - 20 = 25 degree C
specific heat capacity of wood = 1700 J/kg C
specific heat capacity of aluminium = 900 J/kg C
now here we will find the total heat to raise the temperature of both




So heat required to raise the temperature of the system is 257500 J
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
Answer:
áp dụng công thức í, mình thấy câu này có rắc rối gì đâu
Answer:
D. the same as force. the applied force per cross-sectional area.
Explanation:
Tensile stress of a material is defined as the ratio of the applied force on the material to its cross sectional area. this is expressed mathematically as;
Tensile stress = Force/cross sectional area
Tensile stress = F/A
Force is measured in newton while cross sectional area is measured in m
Hence the unit of Tensile stress is N/m²