Answer:
the angle of incidence θ is 45.56 º
Explanation:
Given data
strikes the mirror before wall x = 30.7 cm
reflected ray strikes the wall y = 30.1 cm
to find out
the angle of incidence θ
solution
let us consider ray is strike at angle θ so after strike on surface ray strike to wall at angle 90 - θ
we will apply here right angle triangle rule that is
tan( 90 - θ) = y /x
tan( 90 - θ) = 30.1 / 30.7
90 - θ = tan^-1 (30.1/30.7)
90 - θ = 44.4345
θ = 45.56 º
the angle of incidence θ is 45.56 º
Answer:
it is True as the operational definition of electric current.
Explanation:
The definition of electric current is
I = dQ / dt
By convention the direction of the current is the direction in which a positive charge flows.
The initial expression is the derivative that is the change of the load in the unit of time and this occurs in a given cross-sectional cable.
The proposed definition is the same as this, so it is True as the operational definition of electric current.
Answer:
B) PbI2 + 2 KCl
Explanation:
To keep the the law of conservation of matter, the equation given above must be balanced i.e the total element in the reactant must be equal to the total elements in the product.
Given the equation
PbCl2 (aq) + 2 KI (aq) →
At the reactant shown, there are one mole of lead Pb, 2 moles of chlorine Cl, 2moles of Potassium K and 2 moles of Iodine.
During reaction, the Chlorine atom will react with the potassium atom K and the lead atom Pb will react with the iodine atom.
The resulting product that will balance the chemical equation is
PbI2 + 2 KCl
The equation will then become
PbCl2 (aq) + 2 KI (aq) → PbI2 + 2 KCl
If we look at both sides of the equation, we will see that all the elements have the same number of atoms.
The formulas are-
a=f/m
f=ma
m=f/a