Answer:
θ = 10.28º
Explanation:
To find the angle of refraction use the equation of refraction
n₁ sin θ₁ = n₂ sin θ₂
where index 1 is for incident light and index 2 is for refracted light.
sin θ₂ = n₁ / n₂ sin θ
let's calculate
sin = 1 / 1.3 sin 0.23
sin = 0.175
θ= 0.17528 rad
let's reduce to degrees
θ = 0.17528 rad (180ª / pi rad)
θ = 10.28º
Answer: 100cm
Explanation:
The force of friction on a surface normal to gravity where µ is the coefficient of friction is
F = µmg
Where
F = the friction force
µ = coefficient of friction
m = mass of the object
g = acceleration due to gravity
Also, the Kinetic Energy of the object, E = Fs, where
E = Kinetic Energy
s = stopping distance. So that,
E = µmgs
40 J = 0.4 * 10 kg * 10 m/s² * s
40 J = 40 kgm/s² * s
s = 40 J / 40 kgm/s²
s = 1 m or 100 cm
<h2>
Answer: The half-life of beryllium-15 is 400 times greater than the half-life of beryllium-13.</h2>
Explanation:
The half-life
of a radioactive isotope refers to its decay period, which is the average lifetime of an atom before it disintegrates.
In this case, we are given the half life of two elements:
beryllium-13: 
beryllium-15: 
As we can see, the half-life of beryllium-15 is greater than the half-life of beryllium-13, but how great?
We can find it out by the following expression:

Where
is the amount we want to find:


Finally:

Therefore:
The half-life of beryllium-15 is <u>400 times greater than</u> the half-life of beryllium-13.