Ice causes a crack to form in a rock. This is an example of

What makes a substance, such as<br> aluminum, a good conductor?

spin [16.1K]

Answer:

For a material to be a good conductor, the electricity passed through it must be able to move the electrons; the more free electrons in a metal, the greater its conductivity.

8 0

2 years ago

A dart is thrown at a dartboard 3.66 m away. When the dart is released at the same height as the center of the dartboard, it hit

lapo4ka [179]

Answer:

The angle is $\theta = 15.48^o$

Explanation:

From the question we are told that

The distance of the dartboard from the dart is $d = 3.66 \ m$

The time taken is $t = 0.455 \ s$

The horizontal component of the speed of the dart is mathematically represented as

$u_x = ucos \theta$

where u is the the velocity at dart is lunched

so

$distance = velocity \ in \ the\ x-direction * time$

substituting values

$3.66 = ucos \theta * (0.455)$

=> $ucos \theta = 8.04 \ m/s$

From projectile kinematics the time taken by the dart can be mathematically represented as

$t = \frac{2usin \theta }{g}$

=> $usin \theta = \frac{g * t}{2 }$

$usin \theta = \frac{9.8 * 0.455}{2 }$

$usin \theta = 2.23$

=> $tan \theta = \frac{usin\theta }{ucos \theta } = \frac{2.23}{8.04}$

$\theta = tan^{-1} [0.277]$

$\theta = 15.48^o$

4 0

3 years ago

A spiral spring has a length of 14 cm when a force of 4 N is hung on it. A force of 6 N extends

stira [4]

Answer:

bussy

Explanation:

shart

5 0

1 year ago

¿Cuál es la masa de un objeto cuya masa es de 400 J y energía cinética de 107J?

Pachacha [2.7K]

Answer:

Mass, m = 125 kg

Explanation:

Let us assume that the question says, "What is the mass of an object whose velocity is 400 m/s and the kinetic energy of 10⁷ J.

The kinetic energy of an object is :

$K=\dfrac{1}{2}mv^2\\\\m=\dfrac{2K}{v^2}\\\\m=\dfrac{2\times 10^7}{(400)^2}\\\\m=125\ kg$

So, the mass of the object is 125 kg.

3 0

3 years ago

1. What kind of light phenomena happen due to the refraction of light upon hitting the small crystals that make up cirrus or cir

Rama09 [41]

1. The light phenomena happen due to the refraction of light upon hitting the small crystals that make up cirrus or cirrostratus clouds is called Sundogs.

2.A light phenomena which are formed when light passes through clouds and strikes the ice crystals in them is called Halos.

3.A light phenomenon formed from the combination of several light properties like refraction, reflection, and dispersion is Rainbow.

4. Rainbow are created after a rain shower and Sun light.

5. A visible accumulations of tiny water droplets or ice crystals.

in the Earth’s atmosphere are called Clouds.

6. There are seven colors in a rainbow.

7. The kind of rainbows are formed when light strikes small raindrops with almost the same size are Supernumerary rainbows.

8.The kind of rainbows are formed when two inner reflections are done instead of one; this causes the reversal of colors in a secondary rainbow in comparison to a primary rainbow are Secondary rainbows.

9. A reflective surface that is curved inward and away from the light source is concave mirror.

10. The kind of mirror are curved outward like the bottom

of a spoon is convex mirror.

<h3>What is reflection?</h3>

When a light strikes on a shiny surface, it reflects back the light ray in the same medium. The phenomenon is called reflection and the ray is called the reflected ray.

Thus, all the questions are answered.

Learn more about reflection.

brainly.com/question/2254222

#SPJ1

8 0

1 year ago