The correct answer would be the last one
Answer:
457.81 Hz
Explanation:
From the question, it is stated that it is a question under Doppler effect.
As a result, we use this form
fo = (c + vo) / (c - vs) × fs
fo = observed frequency by observer =?
c = speed of sound = 332 m/s
vo = velocity of observer relative to source = 45 m/s
vs = velocity of source relative to observer = - 46 m/s ( it is taking a negative sign because the velocity of the source is in opposite direction to the observer).
fs = frequency of sound wave by source = 459 Hz
By substituting the the values to the equation, we have
fo = (332 + 45) / (332 - (-46)) × 459
fo = (377/ 332 + 46) × 459
fo = (377/ 378) × 459
fo = 0.9974 × 459
fo = 457.81 Hz
No, the speed at which an object falls is not equal to the acceleration at which it falls.
Answer:
Option B
Explanation:
Speed is defined as how fast an object can cover a specific distance and in what time it covers. So it is measured as the ratio of distance covered to the time taken to cover that distance. While acceleration is the rate of change of velocity. Moreover, speed is a scalar quantity and acceleration is a vector quantity. So most of the times, the direction will play an important role in the varying values of speed and acceleration. Also, acceleration of an object will depend upon the force and mass of the object. Thus, speed and acceleration will not attain same value always.
The force constant of the spring is determined as 14,222.2 N/m.
<h3>Force constant of the spring</h3>
Apply the principle of conservation of energy,
K.E = U
where;
- K.E kinetic energy of the elevator
- U is elastic potential energy of the spring
¹/₂mv² = ¹/₂kx²
mv² = kx²
k = mv²/x²
Where;
- m is mass of the elevator
- v is speed
- x is compression of the spring
k = (2000 x 8²)/(3²)
k = 14,222.2 N/m
Thus, the force constant of the spring is determined as 14,222.2 N/m.
Learn more about force constant here: brainly.com/question/1968517
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Answer:
1. B
2. B
Explanation:
1. he was the only teacher at that time that figured out that everything doesn't revolve around us. he figured it out by a telscope he made from three lens and a tube. its actually pretty cool. He found out that venus first was in front of us.
2. if the earth wasn't at a tilt, then we wouldn't have sessons, when the earth rotate around the sun, the earth is roataing at a title axis. and that changes our seesons, because if we are in south america, and we are in winter time, and south america is cold, then it means that the continent is not getting as much heat from the sun. Does that makes since, because it doesn't sound like it?
