Answer:
Mechanical waves need matter to transfer energy while electromagnetic waves do not. ... Waves change direction when they move from one material into another (matter) through the process of refraction. The wave will change direction when the speed of the wave changes.
D=at²
441m=(5*9.81m/s²)(t²)
t²=441/(5*9.81)
t≈√8.99
t≈3 sec
Answer:
kinetic energy will change by a factor of 1/2
Option C) 1/2 is the correct answer
Explanation:
Given the data in the question;
we know that;
Kinetic energy = 1/2.mv²
given that mass of the object is doubled; m1 = 2m
speed is halved; v1 = V/2
Now, New kinetic energy will be; 1/2.m1v1²
we substitute
Kinetic Energy = 1/2 × 2m × (v/2)²
Kinetic Energy = 1/2 × 2m × (v²/4)
Kinetic Energy = 1/2 × m × (v²/2)
Kinetic Energy = 1/2 [ 1/2mv² ]
Kinetic Energy = 1/2 [ KE ]
Therefore; kinetic energy will change by a factor of 1/2
Option C) 1/2 is the correct answer
<span>The answer is 62 u. The molecular mass of a molecule (Mr) is the sum of atomic masses (Ar) of its elements. Ar(Na) = 23 u. Ar(O) = 16 u. Therefore, the molecular mass of sodium oxide is 62 u: Mr(Na2O) = 2 * Ar(Na) + Ar(O) = 2 * 23 u + 16 u = 46 + 16 = 62 u.</span>