Determine the change in velocity of a car that start at rest and has a final velocity of 20 m/s north

The driver of a car traveling at 23.1 m/s applies the brakes and undergoes a constant

Vsevolod [243]

Answer:

The tires make 125 revolutions before the car stops

Explanation:

Circular and Linear Motion

A tire rotates around a fixed point and the tire when in contact with the ground, drives a vehicle in a linear path. This is an example of a relationship between both types of movements that can be taking place simultaneously.

The car is moving with an initial speed of $v_o=23.1\ m/s$ and then breaks at $a=-1.03\ m/s^2$ until it stops. We can compute the time take to stop by using

$\displaystyle v_f=v_o+a.t$

Solving for t

$\displaystyle t=\frac{v_f-v_o}{a}$

Putting in numbers

$\displaystyle t=\frac{0-23.1}{-1.03}$

$\displaystyle t=22.427\ sec$

Now, let's transfer this information to the circular motion. We know the tangent speed is

$\displaystyle v_t=w.r$

Being w the angular speed and r the radius of the circle, in this case, the tires. The tangent speed is the same as the speed of motion of the car. It gives us the initial angular speed

$\displaystyle w_o=\frac{v_t}{r}$

$\displaystyle w_o=\frac{23.1}{0.33}=70\ rad/s$

When the circular motion is not uniform, i.e. there is angular acceleration $\alpha$ , the angular speed is a function of time

$\displaystyle w=w_o+\alpha t$

We can compute the angular acceleration knowing the final angular speed is zero when the car stops.

$\displaystyle \alpha=\frac{w-w_o}{t}=\frac{0-70}{22.427}$

$\displaystyle \alpha=-3.121\ rad/s^2$

The rotation angle is also a function of time as shown

$\displaystyle \theta=w_o\ t+\frac{\alpha t^2}{2}$

Using the given and computed values

$\displaystyle =70(22.427)-\frac{3.121(22.427)^2}{2}$

$\displaystyle \theta =784.95\ rad$

Knowing each revolution is $2\pi$ radians, the number of revolutions is

$\displaystyle n=\frac{\theta }{2\pi}=125\ rev$

The tires make 125 revolutions before the car stops

8 0

3 years ago

Please help with number 2

Norma-Jean [14]

Number 2 is Classify

Hope this helps!

5 0

3 years ago

A proton is confined in an infinite square well of width 10 fm. (The nuclear potential that binds protons and neutrons in the nu

kvasek [131]

Answer:

First Question

$E = 1.065*10^{-12} \ J$

Second Question

The wavelength is for an X-ray

Explanation:

From the question we are told that

The width of the wall is $w = 10\ fm = 10*10^{-15 }\ m$

The first excited state is $n_1 = 2$

The ground state is $n_0 = 1$

Gnerally the energy (in MeV) of the photon emitted when the proton undergoes a transition is mathematically represented as

$E = \frac{h^2 }{ 8 * m * l^2 [ n_1^2 - n_0 ^2 ] }$

Here h is the Planck's constant with value $h = 6.62607015 * 10^{-34} J \cdot s$

m is the mass of proton with value $m = 1.67 * 10^{-27} \ kg$

So

$E = \frac{( 6.626*10^{-34})^2 }{ 8 * (1.67 *10^{-27}) * (10 *10^{-15})^2 [ 2^2 - 1 ^2 ] }$

=> $E = 1.065*10^{-12} \ J$

Generally the energy of the photon emitted is also mathematically represented as

$E = \frac{h * c }{ \lambda }$

=> $\lambda = \frac{h * c }{E }$

=> $\lambda = \frac{6.62607015 * 10^{-34} * 3.0 *10^{8} }{ 1.065 *10^{-15 } }$

=> $\lambda = 1.87*10^{-10} \ m$

Generally the range of wavelength of X-ray is $10^{-8} \to 1)^{-12}$

So this wavelength is for an X-ray.

8 0

2 years ago

Who invented the cellphone

wel

Martin Cooper invented the cell phone

7 0

3 years ago

Read 2 more answers

The Solar System is made up of eight planets, numerous comets, asteroids, and moons, and the Sun. The force that holds all of th

Marrrta [24]

Your Question:
<span>The Solar System is made up of eight planets, numerous comets, asteroids, and moons, and the Sun. The force that holds all of these objects together is _______.
A.
magnetism
B.
tension
C.
electromagnetic attraction
D.
gravity </span>
Our Teams Answer:

the force is gravity holding them

Our Teams aim's to please and We are happy to help! Its the answer is wrong please notify us quickly for we can fix it quickly! Thanks :)

-ExperimentsDIY

7 0

3 years ago

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