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
Answer:
139.6m/s
Explanation:
Calculate the tension first, T=m*g
mass(m): 1750kg, gravity(g): 9.8m/s^2
T= 1750*9.8
=17150N
Then calculate the wave speed using the equation v = √ (T/μ)
v= √(17150N)/(0.88kg/m)
=139.6m/s
Answer:
E
Explanation:
A vector is a physical quantity that has magnitude and direction while a scalar is a physical quantity that has magnitude only
*electric potential is a scalar quantity because it only has magnitude
*electric field and electric force are vector quantities because they have magnitude and direction
Answer:
a motor is used to covert electrical energy to mechanical energy