Answer
given,
frequency from Police car= 1240 Hz
frequency of sound after return = 1275 Hz
Calculating the speed of the car = ?
Using Doppler's effect formula
Frequency received by the other car
..........(1)
u is the speed of sound = 340 m/s
v is the speed of the car
Frequency of the police car received
now, inserting the value of equation (1)
1.02822(340 - v) = 340 + v
2.02822 v = 340 x 0.028822
2.02822 v = 9.799
v = 4.83 m/s
hence, the speed of the car is equal to v = 4.83 m/s
Once the car is on top of the hill it contains potential energy witch means it is storing enough energy to slide the hill until acted on. Once the car moves and slides down the hill it creates kinetic energy witch means it's in motion. The car then turns the kinetic energy into mechanical energy witch means it's working. I'm not sure if that helped but good luck!
Answer:
The magnitude = 10.30 m
The direction of the vector proceeds at angle of 119.05°
Explanation:
Given that:
A vector 
has component 
= -5 m and 
= 9 m
The magnitude of vector can be represented as:
= 
= 
= 
= 
= 10.30 m
If we make an angle 
with y- axis:
Then; tan = 
tan = 
tan = 0.555
= tan⁻¹ (0.555)
= 29.05°
Angle with positive x-axis = 90 +
= 90° + 29.05°
= 119.05°
Answer:
C
Explanation:
When a ball rolls down a hill, Potential Energy Conversion takes place to Kinetic Energy.
