Answer: velocity of the car is 113.33m/s
Explanation:
From Doppler effect,
in the case which the source is moving towards the observer at rest
f2 = v/(v-vs) *f1
where f2 is the final observed frequency
f1 is the initial observed frequency
v = 340m/s (speed of sound in air)
vs = velocity of the source of sound.
rearranging the above equation
f2*(v - vs) = f1* v
vs = (f1* v/f2) - v
but f1 = 80Hz
f2 = 60Hz
v = 340m/s
substituting,
vs = (80 x 340)/60 - 340
vs = 453.33 - 340
vs = 113.33m/s
velocity of the car is 113.33m/s
m x h x 9.8 m/s squared
70 kg x 3 m x 9.8 m/s squared= 2058 Joules
The description of the question provided above points out to the famous Big Bang Theory. In addition, this theory is among the most accepted by cosmologists because it fits like a glove to the phenomenon the universe is experiencing right now: it is expanding and distances between celestial bodies are getting farther and farther.
Answer:
The correct answer is D.
D:The surface of the coating allows light from the room to pass through but blocks the light from the screen.
Explanation:
Glare is produced on a computer screen when light from some external source reflects on the screen.
Anti-glare coating do not absorb light to reduce glare but they actually reduce glare by encouraging the light from the room to pass through the screen so that less light is reflected. Polarized lenses absorbs light to reduce glare, not anti-glare coating.
Explanation:
C one is the correct one according to me