The index of refraction of a material is the ratio between the speed of light in vacuum, c, and the speed of light in that material, v:

where the speed of light in vacuum is

. The speed of light in benzene is

, so we can use the previous relationship to find the refractive index of benzene:
Answer:
75.6J
Explanation:
Hi!
To solve this problem we must use the first law of thermodynamics that states that the heat required to heat the air is the difference between the energy levels of the air when it enters and when it leaves the body,
Given the above we have the following equation.
Q=(m)(h2)-(m)(h1)
where
m=mass=1.3×10−3kg.
h2= entalpy at 37C
h1= entalpy at -20C
Q=m(h2-h1)
remember that the enthalpy differences for the air can approximate the specific heat multiplied by the temperature difference
Q=mCp(T2-T1)
Cp= specific heat of air = 1020 J/kg⋅K
Q=(1.3×10−3)(1020)(37-(-20))=75.6J
1km per 5 mins
PLEASE VERIFY WITH SOMEONE I MAY BE INCORRECT
Answer:
No. of laps of Hannah are 7 (approx).
Solution:
According to the question:
The total distance to be covered, D = 5000 m
The distance for each lap, x = 400 m
Time taken by Kara, 
Time taken by Hannah, 
Now, the speed of Kara and Hannah can be calculated respectively as:


Time taken in each lap is given by:



t = 500 s
So, Distance covered by Hannah in 't' sec is given by:


No. of laps taken by Hannah when she passes Kara:

≈ 7 laps
Answer:
The speed is
.
(a) is correct option.
Explanation:
Given that,
Potential difference 
Speed 
If it were accelerated instead
Potential difference 
We need to calculate the speed
Using formula of initial work done on proton

We know that,


Put the value into the formula

....(I)
If it were accelerated instead through a potential difference of
, then it would gain a speed will be given as :
Using an above formula,

Put the value of 



Hence, The speed is
.