there are 1.6 km in a mile. the distance between two cities is 248 miles. How many kilometers apart are the two cities?

Most metals are good electrical conductors because (5 points) they hold their electrons they have a large amount of free electro

Hunter-Best [27]

Answer:

Metals are good conductors of electricity <u>because they have free electrons</u> which help in the transfer of charge from one point to another.

6 0

3 years ago

A solid, uniform disk of radius 0.250 m and mass 45.2 kg rolls down a ramp of length 5.40 m that makes an angle of 17.0° with th

serious [3.7K]

Explanation:

Given that,

Radius of the disk, r = 0.25 m

Mass, m = 45.2 kg

Length of the ramp, l = 5.4 m

Angle made by the ramp with horizontal, $\theta=17^{\circ}$

Solution,

As the disk starts from rest from the top of the ramp, the potential energy is equal to the sum of translational kinetic energy and the rotational kinetic energy or by using the law of conservation of energy as :

(a) $mgh=\dfrac{1}{2}mv^2+\dfrac{1}{2}I\omega^2$

h is the height of the ramp

$sin\theta=\dfrac{h}{5.4}$

$h=sin(17)\times 5.4=1.57\ m$

v is the speed of the disk's center

I is the moment of inertia of the disk,

$I=\dfrac{1}{2}mr^2$

$\omega=\dfrac{v}{r}$

$mgh=\dfrac{1}{2}mv^2+\dfrac{1}{2}\dfrac{1}{2}mr^2\times (\dfrac{v}{r})^2$

$gh=\dfrac{1}{2}v^2+\dfrac{1}{4}v^2$

$gh=\dfrac{3}{4}v^2$

$9.8\times 1.57=\dfrac{3}{4}v^2$

v = 4.52 m/s

(b) At the bottom of the ramp, the angular speed of the disk is given by :

$\omega=\dfrac{v}{r}$

$\omega=\dfrac{4.52}{0.25}$

$\omega=18.08\ rad/s$

Hence, this is the required solution.

4 0

3 years ago

How does gay-lussac's law apply to everyday life?

vladimir2022 [97]

Gay-Lussac's Law shows the direct relationship between pressure and temperature for an ideal gas with constant volume. Mathematically it is
$\frac{P_{1}}{T_{1}} = \frac{P_{2}}{T_{2}}$

This particular has a lot of application in our everyday life. In cooking, for example, we apply this concept when using a pressure cooker. We increase/decrease the temperature to meet the right amount of pressure.

In addition, knowing that pressure increases when temperature does can help you with road safety. Knowing that temperature affects heat directly, we must be careful in making sure that tires are not overheated or else they explode out of too much pressure inside.

5 0

3 years ago

Two books with different masses fall off the same bookshelf. As they fall,which has more kinetic energy and why

Alex

Kinetic energy E = m * v^2

<span>Since the acceleration of both books will be -neglecting air resistance - the same, the kinetic energy will be directly proportional to the mass of the book.</span>

5 0

3 years ago

ou are looking for a new tennis partner. Which of these people would most likely demonstrate good sportsmanship based on the inf

Dennis_Churaev [7]

<h2><u>Answer:</u></h2>

As you are looking for a new tennis partner. People should keep in mind that they should go for the one who most likely demonstrate good sportsmanship

Luis, when you pursue the principles in tennis, you realize when to talk up, you don't blast a racquet or shout, holler.

Whatever it is following the principles and being respectful it the most ideal approach.

7 0

3 years ago