Answer:
(d/λ) = 17.67
Explanation:
Equation for double-slit:
d*sinθ = m*λ
Rearrange the equation
(d/λ) = m/(sinθ)
Since it is at the second dark fringe, m = 2
Therefore:
(d/λ) = 2/(sin(6.5)
(d/λ) = 17.67
Answer:
a body which was thrown in space ,moves under the influence of gravity only is defined as projectile.
Recall this gas law:
= 
P₁ and P₂ are the initial and final pressures.
V₁ and V₂ are the initial and final volumes.
T₁ and T₂ are the initial and final temperatures.
Given values:
P₁ = 475kPa
V₁ = 4m³, V₂ = 6.5m³
T₁ = 290K, T₂ = 277K
Substitute the terms in the equation with the given values and solve for Pf:

<h3>P₂ = 279.2kPa</h3>
Answer: The correct explanation is 2.
Explanation: The warm air is less dense (it expands) and thus it is lighter than the cold air so it will rise up to the floor. Therefore, when you place the heater on the floor it will warm the cold air which would then rise and be replaced by more cold air which would again get warm and rise and so on until the room is heated. This means that the correct explanation is 2.
On the other hand, if you put the heater at the ceiling, it will warm the cold air near the ceiling which would stay up there (it is lighter than the cold air under it). This means that the only way for the heat to spread from this ceiling level warm air to the lower levels is via conduction which is slow.