Answer:
0.76
Explanation:
we are given:
radius (r) =5.7 m
speed (s) = 1 revolution in 5.5 seconds
acceleration due to gravity (g) = 9.8 m/s^{2}
coefficient of friction (Uk) = ?
  we can get the minimum coefficient of friction from the equation below
centrifugal force = frictional force
m x r x ω^{2} = Uk x m x g
r x ω^{2} = Uk x g
Uk = 
where ω (angular velocity) = 
=  = 1.14
 = 1.14
Uk =  = 0.76
 = 0.76
 
        
             
        
        
        
The minimum potential difference must be supplied by the ignition circuit to start a car is -1800 V
<u>Explanation:</u>
Given data,
E= 3 ×10 ⁶ Δx=0.06/100
We have to find the minimum potential difference
E= -ΔV/Δx
ΔV=- E × Δx
ΔV =-3 ×10 ⁶ . 0.06/100
 ΔV=-1800 V 
The minimum potential difference must be supplied by the ignition circuit to start a car is -1800 V
 
        
             
        
        
        
The coefficient of friction must be 0.196
Explanation:
For a car moving on a circular track, the frictional force provides the centripetal force needed to keep the car in circular motion. Therefore, we can write:
 
where the term on the left is the frictional force acting between the tires of the car and the road, while the term on the right is the centripetal force. The various terms are:
 is the coefficient of friction between the tires and the road
 is the coefficient of friction between the tires and the road
m is the mass of the car
 is the acceleration of gravity
 is the acceleration of gravity
v is the speed of the car
r is the radius of the curve
In this problem,
r = 750 m is the radius
 is the speed
 is the speed
And solving for  , we find the coefficient of friction required to keep the car in circular motion:
, we find the coefficient of friction required to keep the car in circular motion:

Learn more about circular motion:
brainly.com/question/2562955  
brainly.com/question/6372960  
#LearnwithBrainly
 
        
             
        
        
        
Answer:
g / 16 
Explanation:
T = 2π 
 angular frequency ω = 2π /T
= 
ω₁ /ω₂ = 
Putting the values 
ω₁ = ω ,     ω₂ = ω / 4
ω₁ /ω₂ = 4 
4 =  
g₂ = g / 16
option d is correct. 
 
        
             
        
        
        
Answer:
V = 3.5 x 10⁻⁶ m³/s = 3.5 cm³/s
Explanation:
The volume flow rate of the blood in the artery can be given by the following formula:

where,
V = Volume flow rate = ?
A = cross-sectional area of artery = πd²/4 = π(0.004 m)²/4 = 1.26 x 10⁻⁵ m²
v = velcoity = 0.28 m/s
Therefore,

<u>V = 3.5 x 10⁻⁶ m³/s = 3.5 cm³/s</u>