Answer:
B) 2.7W
Explanation:
Converting Cal to Joule
1 cal = 4.186J
14 kcal = 14 x 1000 x 4.186
= 58604 J
Converting hour to seconds
6 hours = 6 x 60 x 60 seconds
= 21600 seconds
Power is the time rate of doing work.
Power = Work/Time
P = (58604) / (21600)
P = 2.7W
143m/s if you just perhaps by what you know you'll figure it out
Answer:
19.08 m/s
Explanation:
f = actual frequency emitted by the parked car's horn = 440 Hz
V = speed of sound = 342 m/s
f' = frequency of the horn observed by you = 466 Hz
v = speed of your car moving towards the parked car = ?
frequency of the horn observed by you is given as
v = 19.08 m/s
Answer:
elements in the same column have the same number of neutrons. elements with similar mass are placed in the same column.
Light that enters the new medium <em>perpendicular to the surface</em> keeps sailing straight through the new medium unrefracted (in the same direction).
Perpendicular to the surface is the "normal" to the surface. So the angle of incidence (angle between the laser and the normal) is zero, and the law of refraction (just like the law of reflection) predicts an angle of zero between the normal and the refracted (or the reflected) beam.
Moral of the story: If you want your laser to keep going in the same direction after it enters the water, or to bounce back in the same direction it came from when it hits the mirror, then shoot it <em>straight on</em> to the surface, perpendicular to it.
