Answer: The frequency heard will be f = 275.675Hz
Explanation: When an object emitting sound is moving, it occurs a phenomenon called Doppler shift or Doppler effect. What happens is that the sound gets higher when the moving object comes closer the observer and becomes lower after it passes, This change is due to the quantity of waves that passes through an area in an unit of time.
The formula to calculate the Doppler effect is as follows
f = (
) · f₀
f is the observed frequency;
c is the speed of sound;
Vs is velocity of the source;
f₀ is the emitted frequency of source;
Substituting and calculating,
f = 
· 300
f = 275.675 Hz
Thus, the frequency heard by the police officer is 275.675Hz.
Explanation:
Linear acceleration is a type of acceleration of a body along a straight path or line.
Acceleration is defined as the rate of change of velocity with time.
Acceleration = 
There are different types of acceleration .
- linear acceleration is used to describe the rate of change of velocity of a body along a straight path with time.
- centripetal acceleration is the rate of change of velocity of a body traveling along a circular path with time. It is directed towards the center.
- Angular acceleration is the rate of change of angular velocity.
Learn more:
Acceleration brainly.com/question/3820012
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The masses of the object and the planet it's on, and the distance between their centers.
Answer:
C)Earth's orbital speed is greater when it is closer to the Sun than when it is farther from the Sun.
Explanation:
We can use Kepler's 2nd law or the law of area to answer this question.
The law states that the rate of area swept out by a planet's orbit is same throughout the orbit. For the farthest point since the distance is large as compared to to the nearest point, the possibility that area swept is large. Hence, to compensate the extra swept area. the orbital speed has to decrease at the largest point.
Hence, planet's speed is greater when it is closer to sun than the speed when it is farther.
When you climb, earth exerts gravitational force on pack in downward direction(pointing towards the center of earth).
In order to climb, you need to work against work done by gravity on the pack.
Hence work done by you = work done by gravity on pack
= Force x displacement = 70 x 30 = 2100 J.
