Answer:
A) d = 11.8m
B) d = 4.293 m
Explanation:
A) We are told that the angle of incidence;θ_i = 70°.
Now, if refraction doesn't occur, the angle of the light continues to be 70° in the water relative to the normal. Thus;
tan 70° = d/4.3m
Where d is the distance from point B at which the laser beam would strike the lakebottom.
So,d = 4.3*tan70
d = 11.8m
B) Since the light is moving from air (n1=1.00) to water (n2=1.33), we can use Snell's law to find the angle of refraction(θ_r)
So,
n1*sinθ_i = n2*sinθ_r
Thus; sinθ_r = (n1*sinθ_i)/n2
sinθ_r = (1 * sin70)/1.33
sinθ_r = 0.7065
θ_r = sin^(-1)0.7065
θ_r = 44.95°
Thus; xonsidering refraction, distance from point B at which the laser beam strikes the lake-bottom is calculated from;
d = 4.3 tan44.95
d = 4.293 m
It depends, because worm holes are theoretical construed of space and time. It hasn’t been proven to exist but mathematically it hasn’t been spotted but we also haven’t been very far in our universe.
So to cut the story short, it is not a proven phenomenon only theoretical.
Answer:
The ball would hit the floor approximately 
after leaving the table.
The ball would travel approximately 
horizontally after leaving the table.
(Assumption: 
.)
Explanation:
Let 
denote the change to the height of the ball. Let 
denote the time (in seconds) it took for the ball to hit the floor after leaving the table. Let 
denote the initial vertical velocity of this ball.
If the air resistance on this ball is indeed negligible:
.
The ball was initially travelling horizontally. In other words, before leaving the table, the vertical velocity of the ball was 
.
The height of the table was 
. Therefore, after hitting the floor, the ball would be 
below where it was before leaving the table. Hence, 
.
The equation becomes:
.
Solve for :
.
In other words, it would take approximately for the ball to hit the floor after leaving the table.
Since the air resistance on the ball is negligible, the horizontal velocity of this ball would be constant (at 
) until the ball hits the floor.
The ball was in the air for approximately 
and would have travelled approximately 
horizontally during the flight.
<span>A student hears a police siren.
The arithmetic of the Doppler Effect shows that if the distance between
the source and observer is changing, then the observer hears a different
frequency compared to the frequency actually radiating from the source.
Thus the first four choices would cause the student to hear a different
frequency:
-- if the student walked toward the police car
-- if the student walked away from the police car
-- if the police car moved toward the student
-- if the police car moved away from the student
The last two choices wouldn't affect the frequency heard by the student,
since the perceived frequency of a sound doesn't depend on its intensity.
-- if the intensity of the siren increased
-- if the intensity of the siren decreased.</span>
Answer:
The magnitude of the electrostatic force decreases by a factor 9
Explanation:
The electrostatic force between two charges is given by:
where
k is the Coulomb's constant
q1 and q2 are the two charges
d is the distance between the two charges
We see that the magnitude of the force is inversely proportional to the square of the distance. If the distance is increased to 3d: d' = 3d, the new electrostatic force would be:
So, the electrostatic force decreases by a factor 9.
