Which is a characteritic of a physical change?

A dentist causes the bit of a high-speed drill to accelerate from an angular speed of 1.50 × 10 4 1.50×104 rad/s to an angular s

KATRIN_1 [288]

Answer:

0.32 s

Explanation:

Initial angular speed: $\omega_i = 1.50 \cdot 10^4 rad/s$

Final angular speed: $\omega_f = 3.35\cdot 10^4 rad/s$

Angular rotation: $\theta=2.02\cdot 10^4 rad$

The angular acceleration of the drill can be found by using the equation:

$\omega_f^2 - \omega_i^2 = 2 \alpha \theta$

Re-arranging it, we find $\alpha$ , the angular acceleration:

$\alpha = \frac{\omega_f^2 - \omega_i^2}{2\theta}=\frac{(3.35\cdot 10^4 rad/s)^2-(1.50\cdot 10^4 rad/s)^2}{2(2.02\cdot 10^4 rad)}=22,209 rad/s^2$

Now we want to know the time t the drill takes to accelerate from

$\omega_i =0$

to

$\omega_f = 6.90\cdot 10^4 rad/s$

This can be found by using the equation

$\omega_f = \omega_i + \alpha t$

where $\alpha$ is the angular acceleration we found previously. Solving for t,

$t=\frac{\omega_f - \omega_i}{\alpha}=\frac{22,209 rad/s^2}{6.90\cdot 10^4 rad/s}=0.32 s$

5 0

3 years ago

What is the direction of the electric field at the corner? What is the direction of the electric field at the corner? along the

ehidna [41]

Answer:

jsjsj isso isso isms sim

Explanation:

jjed djdn djms disse sjsm disse mism

7 0

3 years ago

Which of the following is NOT an example of environmental sustainability practices? Question 4 options: A. Waste management B. S

aivan3 [116]

Sustainable product design is not an example of environmental sustainability.

<u>Explanation: </u>

Development which meets the present needs without compromising the ability of future generations to meet their own needs is known as sustainable development.
For the process of waste management, many lands deposited should be cleaned and preserved properly. Throwing waste in public places or plastics which is not biodegradable can affect the environment as well as living things. Proper disposal of waste should be done and many landfill processes are made for the safety of a clean environment.
Energy optimization is a major key to environmental sustainability. Much renewable energy is practiced to improve the optimization of energy. Resource management is not only environment-related it also helps in improving the ethical, economic and scientific variables.

3 0

4 years ago

An automobile whose speed is increasing at a rate of 0.800 m/s2 travels along a circular road of radius 10.0 m.

Ket [755]

(a) $a_t = 0.800 m/s^2$

The tangential acceleration component of the car is simply equal to the change of the tangential speed divided by the time taken:

$a_t = \frac{\Delta v}{\Delta t}$

This rate of change is already given by the problem, 0.800 m/s^2, so the tangential acceleration of the car is

$a_t = 0.800 m/s^2$

(b) $a_c = 0.9 m/s^2$

The centripetal acceleration component is given by

$a_c = \frac{v^2}{r}$

where

v is the tangential speed

r is the radius of the trajectory

When the speed is v = 3.00 m/s, the centripetal acceleration is (the radius is r = 10.0 m):

$a_c = \frac{(3.00 m/s)^2}{10.0 m}=0.9 m/s^2$

(c) $1.2 m/s^2, 48.4^{\circ}$

The centripetal acceleration and the tangential acceleration are perpendicular to each other, so the magnitude of the total acceleration can be found by using Pythagorean's theorem:

$a=\sqrt{a_t^2+a_c^2}=\sqrt{(0.8 m/s^2)^2+(0.9 m/s^2)^2}=1.2 m/s^2$

and the direction is given by:

$tan \theta =\frac{a_c}{a_t}=\frac{0.9 m/s^2}{0.8 m/s^2}=1.125\\\theta=tan^{-1}(1.125)=48.4^{\circ}$

where the angle is measured with respect to the direction of the tangential acceleration.

4 0

3 years ago

What would decrease the gravitational pull between the sun and Earth?(1 point)

VARVARA [1.3K]

The gravitational pull between the sun and Earth decreases if the sun was farther away from the earth.

<h3>What is Gravitational Force?</h3>

Any two bodies' gravitational pull on one another is directly proportional to the product of their masses and inversely proportional to the square of their distance from one another.

How do the planets move in relation to the Sun? The planets' orbits around the Sun are maintained by the gravity of the Sun. The Moon orbits the Earth due to the Earth's gravitational pull on the Moon for the same reason. But if the Earth is being drawn to the Sun, why doesn't it fall into it or the Moon strike the Earth?

The cause of this is because Earth moves at a speed that is perpendicular to the Sun's gravitational pull. The planets are thus kept in their designated orbits by the Sun's attraction as well as their sideways motion. Similar to how the Earth orbits the Moon, the Moon does so without touching it.

F=G(M1M2)/R² where,

F denotes gravitational force between two bodies,

R is the distance between two bodies from their center,

M1 denotes mass of first body and,

M2 denotes mass of second body.

So according to the question, if the distance between two bodies will increase, then the gravitational force between them will also decrease.

Hence, if the sun was farther away from earth, then gravitational pull between the sun and earth will decrease.

To get more information about Gravitational force :

brainly.com/question/12528243

#SPJ1

3 0

2 years ago