A = 4\pi r^2
A = 4\pi (2\mu m /2)^2 (10^{-6}m/1\mu m)^2 (1mm/10{-3})^2
A = 1.33*!0^{-5}MM^2
Answer:
Explanation:
Force on electron in an electric field E = eE where E is electric field .
acceleration = eE / m where m is mass of electron .
Putting the values
4 x 10⁶ = 1.6 x 10⁻¹⁹ x E / 9.1 x 10⁻³¹
E = 22.75 x 10⁻⁶ N/C
The direction of electric field will be towards west ( opposite to east )
because of negative charge on electron .
The wavelength of a wave (λ) is given by λ
where c is the wave speed and f is the frequency
Answer:
Cp= 0.44 J/g.C
This is heat capacity of metal.
Explanation:
From energy conservation
Heat lost by metal = Heat gain by water +Heat gain by calorimeter
Because here temperature of metal is high that is why it loose the heat.The temperature of water and calorimeter is low that is why they gain the heat.
final temperature is T= 30.5 C
We know that sensible heat transfer given as
Q= m Cp ΔT
m=Mass
Cp=Specific heat capacity
ΔT=Temperature difference
By putting the values
55 x Cp ( 99.5 - 30.5) = 40 x 4.184 ( 30.5- 21 ) + 10 x ( 30.5 - 21)
Cp ( 99 .5- 30.5) = 30.65
Cp= 0.44 J/g.C
This is heat capacity of metal.
