Answer:
(a) The final angular speed is 12.05 rad/s
(b) The time taken to turn 5.5 revolutions is 5.74 s
Explanation:
Given;
number of revolutions, θ = 5.5 revolutions
acceleration of the wheel, α = 20 rpm/s
number of revolutions in radian is given as;
θ = 5.5 x 2π = 34.562 rad
angular acceleration in rad/s² is given as;

(a)
The final angular speed is given as;

(b) the time taken to turn 5.5 revolutions is given as

The resultant of the given forces is; 6√2 N
<h3>How to find the resultant of forces</h3>
We are given the forces as;
10 N along the x-axis which is +10 N in the x-direction
6 N along the y-axis which is +6N in the y-direction
4 N along the negative x-axis which is -4N
Thus;
Resultant force in the x-direction is; 10 - 4 = 6N
Resultant force in the y-direction is; 6N
Thus;
Total resultant force = √(6² + 6²)
Total resultant force = 6√2 N
Read more about finding resultant of a force at; brainly.com/question/14626208
Explanation:
Given that,
Bill is riding his bicycle at 5 m/s eastward: and Carlos is driving his car at 15 m/s westward.
Taking eastward as positive direction, we have:
is the velocity of Bill with respect to Amy (which is stationary)
is the velocity of Carlos with respect to Amy.
Bill is moving 5 m/s eastward compared to Amy at rest, so the velocity of Bill's reference frame is

Therefore, Carlos velocity in Bill's reference frame will be

So, the magnitude is 20 m/s and the direction is westward (negative sign).
Answer: 529.9 Hz
Explanation:
Here we need to use the Doppler equation, so we have:
f' = f*(v + v0)/(v - vs)
Here, f is the frequency = 500Hz
v is the velocity of the wave, = 334m/s
v0 is the velocity of the observer = 20m/s
vs is the velocity of the source = 0m/s
Then we have:
f' = 500Hz*(334m/s + 20m/s)/(334m/s) = 529.9 Hz