Answer:
The answer is <em>e.2</em>
Explanation:
We should make use of Snell's refractive law. The arriving wave has a certain velocity at T in a medium, then instantly it reaches a medium (same composition) at T' where velocity would either decrease or increase.
When the incidence angle is 30 °, and we want to make the refraction angle 90 ° such that no sound passes through the barrier (this would be named total internal refraction), so we want the second medium to be "faster" than in the first.
<em>The steps are in the image attached:</em>
Answer:
100 V
Explanation:
Hi there!
Ohm's law states that
where V is the voltage, I is the current and R is the resistance.
Plug the given information into Ohm's law (R=50, I=A)

Therefore, the voltage across this current is 100 V.
I hope this helps!
Speed= Distance/Time
Distance=24m
Time= 5seconds
Speed= 24/5= 4.8m/s
<h2>
The balloon is moving when it is halfway down the building at 20.78 m/s.</h2>
Explanation:
We have equation of motion v² = u² + 2as
Initial velocity, u = 0 m/s
Acceleration, a = 9.81 m/s²
Displacement, s = 0.5 x 44 = 22 m
Substituting
v² = u² + 2as
v² = 0² + 2 x 9.81 x 22
v² = 431.64
v = 20.78 m/s
Velocity at 22 m = 20.78 m/s
The balloon is moving when it is halfway down the building at 20.78 m/s.