Human activities is the main reason of global warming such as factories and cars that causes carbon dioxide , carbon monoxide and other toxic gases
Given Information:
Frequency of horn = f₀ = 440 Hz
Speed of sound = v = 330 m/s
Speed of bus = v₀ = 20 m/s
Answer:
Case 1. When the bus is crossing the student = 440 Hz
Case 2. When the bus is approaching the student = 414.9 Hz
Case 3. When the bus is moving away from the student = 468.4 Hz
Explanation:
There are 3 cases in this scenario:
Case 1. When the bus is crossing the student
Case 2. When the bus is approaching the student
Case 3. When the bus is moving away from the student
Let us explore each case:
Case 1. When the bus is crossing the student:
Student will hear the same frequency emitted by the horn that is 440 Hz.
f = 440 Hz
Case 2. When the bus is approaching the student
f = f₀ ( v / v+v₀ )
f = 440 ( 330/ 330+20 )
f = 440 ( 330/ 350 )
f = 440 ( 0.943 )
f = 414.9 Hz
Case 3. When the bus is moving away from the student
f = f₀ ( v / v+v₀ )
f = 440 ( 330/ 330-20 )
f = 440 ( 330/ 310 )
f = 440 ( 1.0645 )
f = 468.4 Hz
To solve this problem it is necessary to apply the equations related to the conservation of momentum.
This definition can be expressed as
Where
= Mass of each object
= Initial Velocity of each object
= Final velocity
Rearranging the equation to find the final velocity we have,
Our values are given as
Replacing we have,
Therefore the final velocity is 6.5m/s
The answer is D have a nice day!
Answer:
The work done on the athlete is approximately 2.09 J
Explanation:
From the definition of the work done by a variable force:
and substituting with the function of our problem:
