Answer:
a structural variation in which different atoms of the same element have different numbers of neutrons
Explanation:
An isotope is an atom of an element having the same number of protons but different number of neutrons. Different isotopes are used for different purposes. Example: some are used in medicines , food irradiation, etc.
Carbon has three isotopes C 12, C 13, C 14. All three of them have 6 protons but have different numbers of neutrons.
C 12 is a common element and is abundant in nature
C 13 is less abundant than C 12
C 14 is used for dating fossils . It is radioactive
Answer:
Explanation:
The angle of incidence and refraction are both measured from the normal
angle of incidence = 30°
angle of refraction = 23°
refractive index(n) = sini / sinr
n = sin30°/sin23°
n = 1.27965
refractive index (n) = 1/sinC
where C is the critical angle.
sinC= 1/n
C =arcsin (1/n)
C =arcsin (1/1.27965)
C = 51.39°
Answer:

Now when it will reach at point B then its normal force is just equal to ZERO


Explanation:
Since we need to cross both the loops so least speed at the bottom must be

also by energy conservation this is gained by initial potential energy


so we will have

now we have

here we have
R = 7.5 m
so we have


Now when it will reach at point B then its normal force is just equal to ZERO

now when it reach point C then the speed will be
![mgh - mg(2R_c) = \frac{1}{2]mv_c^2](https://tex.z-dn.net/?f=mgh%20-%20mg%282R_c%29%20%3D%20%5Cfrac%7B1%7D%7B2%5Dmv_c%5E2)


now normal force at point C is given as



Refer to the diagrams shown below.
The normal reaction of the road on the automobile is equal to the weight of the automobile (Newtons 3rd Law).
That is,
N = mg (g = 9.8 m/s²)
When the road surface is dry, the resisting frictional force at the wheel is
F₁ = μ₁N
where
μ₁ = the kinetic coefficient of friction.
The value of μ₁ is about 0.7 - 0.9 on a dry road.
When the road is wet, the resisting frictional force is
F = μ₂N
where
μ₂ = the kinetic coefficient of friction on a wet road.
The value of μ₂ is about 0.1 - 0.4 on a wet road.
Because μ₂ < μ₁, the automobile tends to slip on a wet road, especially if the tires are worn.