All categories

4 years ago

Question 27 (Mandatory) (11 points)

Physics

1 answer:

Lostsunrise [7]4 years ago

4 0

Groups

Same number of valence electrons

Li, Na, K

Explanation:

If the periodic table is not color coded, the groups of elements gives the arrangement of atoms with the same chemical properties.

All elements that are in the same group have the same chemical properties.

Periodic table groups are also called family. They are the vertical columns on the periodic table.

Elements that same number of electrons in outermost shell have the same chemical properties.

The outermost shell is called the valence shell of an atom.

They are the shell containing the most loosely held electrons. Group 1 has just one electron in their outermost shell.

Li Na k group 1

F Cl Br group 7

learn more:

Periodic table brainly.com/question/2014634

Groups brainly.com/question/2690837

#learnwithBrainly

You might be interested in

Lasers are classified according to the eye-damage danger they pose. Class 2 lasers, including many laser pointers, produce visib

Alexus [3.1K]

Answer:

Explanation:

Power of laser P = 1 mW = 1 x 10^-3 W

exposure time t = 250 ms = 250 x 10^-3 s

If beam diameter = 2 mm = 2 x 10^-3 m

then

cross-sectional area of beam A = $\pi d^{2} /4$ = (3.142 x $(2*10^{-3} )^{2}$ )/4

A = 3.142 x 10^-6 m^2

a) Intensity I = P/A

where P is the power of the laser

A is the cros-sectional area of the beam

I = ( 1 x 10^-3)/(3.142 x 10^-6) = <em>318.2 W/m^2</em>

b) Total energy delivered E = Pt

where P is the power of the beam

t is the exposure time

E = 1 x 10^-3 x 250 x 10^-3 = <em>2.5 x 10^-4 J</em>

c) The peak electric field is given as

E = $\sqrt{2I/ce_{0} }$

where I is the intensity of the beam

E is the electric field

c is the speed of light = 3 x 10^8 m/s

$e_{0}$ = 8.85 x 10^9 m kg s^-2 A^-2

E = $\sqrt{2*318.2/3*10^8*8.85*10^9}$ = <em>1.55 x 10^-8 v/m</em>

6 0

4 years ago

The coefficient of static friction between a 3.00 kg crate and the 35.0o incline is 0.300. What minimum force F must be applied

Yakvenalex [24]

Answer:

So the minimum force is

32.2Newton

Explanation:

To solve for the minimum force, let us assume it to be F (N)

F=mgsinA

But

=>>>> coefficient of static friction x (F + mgcosA

=>3 x 9.8 x sin35 = 0.3 x (F + 3 x 9.8 x cos35)

So making F subject of formula

F + 24.0 = 56.2

F = 32.2N

3 0

3 years ago

Modern oil tankers weigh over a half-million tons and have lengths of up to one-fourth mile. Such massive ships require a distan

sergiy2304 [10]

(a) $-1.46\cdot 10^{-4} m/s^2$

The average acceleration of the ship is given by

$a=\frac{v-u}{t}$

where

v is the final velocity

u is the initial velocity

t is the time elapsed

Here we have:

$u=34 km/h =9.44 m/s$ is the initial velocity

v = 0 is the final velocity

$t=18 min =64800 s$ is the time elapsed

Substituting, we find

$a=\frac{0-9.44 m/s}{64800 s}=-1.46\cdot 10^{-4} m/s^2$

(b) 4.72 m/s

Assuming the acceleration is uniform, the average velocity of the ship is given by:

$v_{avg} = \frac{v+u}{2}$

where

v is the final velocity

u is the initial velocity

Here we have:

v = 0

u = 9.44 m/s

So the average velocity of the ship is

$v_{avg} = \frac{0+9.44 m/s}{2}=4.72 m/s$

6 0

4 years ago

2. Which energy sources (input) cause the solar panels to generate electrical energy?

Daniel [21]

Answer:

Explanation:

<h2>In the case of artificial photosynthesis, the energy input used to generate the required electricity is solar energy. The optical solar energy is converted into electricity inside the material system using the same scientific principles as PV modules.</h2><h2>Hope it will help</h2>

7 0

4 years ago

Which type of graph uses wedges to show the amount of data points in a category?

Umnica [9.8K]

A pie chart uses wedges to show the amount of data points in a category.

8 0

4 years ago

Read 2 more answers