<span>In general the route that follows the 1100-m-high alpe d'huez mountain stage takes anywhere from four to six hours in athletes from around the world. A beginner would probably take 8 hours or so. World records were recently broken with a time just under three hours. The most friction for cyclist is the competition itself.</span>
R is proportional to the length of the wire:
R ∝ length
R is also proportional to the inverse square of the diameter:
R ∝ 1/diameter²
The resistance of a wire 2700ft long with a diameter of 0.26in is 9850Ω. Now let's change the shape of the wire, adding and subtracting material as we go along, such that the wire is now 2800ft and has a diameter of 0.1in.
Calculate the scale factor due to the changed length:
k₁ = 2800/2700 = 1.037
Scale factor due to changed diameter:
k₂ = 1/(0.1/0.26)² = 6.76
Multiply the original resistance by these factors to get the new resistance:
R = R₀k₁k₂
R₀ = 9850Ω, k₁ = 1.037, k₂ = 6.76
R = 9850(1.037)(6.76)
R = 69049.682Ω
Round to the nearest hundredth:
R = 69049.68Ω
Answer:
27 m/s²
Explanation:
Traveling in uniform circular motion will cause a centripetal acceleration, an acceleration towards the center of the circle.
The acceleration of an object in circular motion is defined as a = v²/r.
Let's set the radius to be 5 m, since it is always unchanging. Solving for the velocity using a = 3 m/s² and r = 3 m gives us:
The velocity is 3 m/s when the acceleration is 3 m/s² and the radius of the circular path is 3 m.
Now let's triple the velocity: 3 m/s → 9 m/s.
Let's solve for the acceleration using v = 9 m/s and r = 3 m.
- a = (9)²/3
- a = 81/3
- a = 27
The acceleration is 27 m/s² if you triple your speed.
This makes sense because a is directly proportional to v², meaning that if you triple your speed, you increase the acceleration a by a factor of 3², which is a 9 times increase.
As a sidenote, doubling your speed would increase the acceleration by a factor of 2² - a 4 times increase.
By writing kinematic equations you can find the answer.
The acceleration is:
a = g
The speed is:
v = a * t
v = g * t
Note that as time passes, speed increases.
When increasing the speed, the resistance of the air is greater.
answer:
air resistance increases
