Answer:
y = 1.19 m and λ = 8.6036 10⁻⁷ m
Explanation:
This is a slit interference problem, the expression for destructive interference is
d sin θ = m λ
indicate that for the angle of θ = 35º it is in the third order m = 3 and the separation of the slits is d = 4.50 10⁻⁶ m
λ = d sin θ / m
let's calculate
λ = 4.50 10⁻⁶ sin 35 /3
λ = 8.6036 10⁻⁷ m
for the separation distance from the central stripe, we use trigonometry
tan θ= y / L
y = L tan θ
the distance L is measured from the slits, it indicates that the light source is at x = 0.30 m from the slits
L = 2 -0.30
L = 1.70 m
let's calculate
y = 1.70 tan 35
y = 1.19 m
Answer: The poker stick should have low thermal conductivity and high specific heat.
Explanation: For a poker stick that is non flammable, it should have some properties which will not let it heat up faster.
Two properties that satisfy the poker stick are:
- Specific heat
- Thermal conductivity
Specific heat is defined as the amount of heat require to raise the temperature of a mass M by 1 °C. More the specific heat, more amount of heat will be required to raise the temperature of a substance.
Thermal conductivity is defined as the ability of a substance to conduct heat. More thermal conductivity means that the substance will get hot faster as it will conduct more amount of heat.
So, for a substance that should not conduct more heat like the poker stick must have high specific heat and low thermal conductivity.
Even though all materials are at the same temperature when they come out of the dryer, some like the zipper are far better conductors of heat and can burn you. Cloth is not a good conductor of heat.
