All categories

3 years ago

PLEASE HELP!! WILL MARK THE BRAINLIEST! HIGH SCHOOL PHYSICAL SCIENCE

Physics

1 answer:

Gemiola [76]3 years ago

6 0

Answer:

Periods indicate that a new period at a new principal energy level which is filled with electrons. Groups indicate that the elements share similar properties because their shells are filled with the same number of valence electons.

Explanation:

e see that starting at period 2 Li has a +1 charge , He has +2 charge, B has +3 charge, C has the potential to have a +4 charge or -4 charge (because it can gain or loose electrons) and N has a -3 charge, etc. Groups however, have similar properties and every element in a 1A - 8A has the same number of valence electrons. All except the noble gases in which He only needs 2 electrons to be in a perfect state. This is its octet as it would be a completely different element if it had more than 2 electrons in its shell. An example of the groups sharing similar properties is if we were to look at group 1A. In group 1A we find H, Na, K, etc. These are all highly unstable elements when alone (not in a compound) and they are very reactive. If you were to put Na for instance in water, it would light up and you'd see a flame sitting on top of the water. A scientist could do that with the rest of the elements in the group and they would see this increasing in reactivity as you go down the periods. Francium isn't visible long enough to be able to see this happen though. It's more of that kind of element that scientists prove that it exists, but not a very common element to get to learn much about.

You might be interested in

Imagine that a hypothetical life form is discovered on our moon and transported to Earth. On a hot day, this life form begins to

almond37 [142]

Answer:

The heat of vaporization 580 cal/g times 602g = cal in human and do the same for life form.

Explanation:

4 0

4 years ago

A force of 5 n produces an acceleration of 8m/s2 in mass m1 and an acceleration of 24 m/s2 in mass m2 .what acceleration would i

Inessa [10]

Acceleration of the both masses tied together= 6m/s²

Explanation:

The force is given by F= ma

so 5= m1 (8)

m1=0.625 Kg

for m2

5=m2 (24)

m2=0.208 kg

now total mass= m1+m2=0.625+0.208

Total mass=M=0.833 Kg

now F= ma

5= 0.833 (a)

a= 5/0.833

a=6m/s²

4 0

4 years ago

1. Bone has a Young’s modulus of about

Blababa [14]

As we know that

$Y = \frac{stress}{strain}$

now plug in all data into this

$1.8\times 10^{10} = \frac{1.68 \times 10^8}{strain}$

$strain = 9.33 \times 10^{-3}$

now from the formula of strain

$strain = \frac{\Delta L}{L}$

$9.33 \times 10^{-3} = \frac{\Delta L}{0.54}$

$\Delta L = 5.04 \times 10^{-3} m$

$\Delta L = 5.04 mm$

As we know that

pressure * area = Force

here we know that

$Area = 3.53 \times 11.6 = 40.95 m^2$

$P = 0.2 atm = 0.2 \times 1.01 \times 10^5 = 2.02\times 10^4 Pa$

now force is given as

$F = 40.95 \times (2.02\times 10^4) = 8.27 \times 10^5 N$

As we know that density of water will vary with the height as given below

$\rho = \frac{\rho_0}{1 - \frac{\Delta P}{B}}$

here we know that

$\Delta P = 2600 atm = 2600 \times 1.01 \times 10^5 = 2.63\times 10^8 Pa$

$B = 2.3 \times 10^9 N/m^2$

now density is given as

$\rho = \frac{1050}{1 - \frac{2.63\times 10^8}{2.3 \times 10^9}}$

$\rho = 1185.3 kg/m^3$

as we know that pressure changes with depth as per following equation

$P = P_o + \rho g h$

here we know that

$P = 3 P_0$

now we will have

$3P_0 = P_0 + \rho g h$

$2P_0 = \rho g h$

$2(1.01 \times 10^5) = 1025 (9.81)(h)$

here we will have

$h = 20.1 m$

so it is 20.1 m below the surface

Here net buoyancy force due to water and oil will balance the weight of the block

so here we will have

$mg = \rho_1V_1g + \rho_2V_2g$

$A(0.0476)979 = 922(A)(0.0476 - x) + 1000(A)(x)$

$46.6 = 43.89 - 922x + 1000x$

$x = 3.48 cm$

so it is 3.48 cm below the interface

5 0

4 years ago

A stretched string has a mass per unit length of 5.40 g/cm and a tension of 17.5 N. A sinusoidal wave on this string has an ampl

kondaur [170]

Answer:

Part a)

$y_m = 0.157 mm$

part b)

$k = 101.8 rad/m$

Part c)

$\omega = 579.3 rad/s$

Part d)

here since wave is moving in negative direction so the sign of $\omega$ must be positive

Explanation:

As we know that the speed of wave in string is given by

$v = \sqrt{\frac{T}{m/L}}$

so we have

$T = 17.5 N$

$m/L = 5.4 g/cm = 0.54 kg/m$

now we have

$v = \sqrt{\frac{17.5}{0.54}}$

$v = 5.69 m/s$

now we have

Part a)

$y_m$ = amplitude of wave

$y_m = 0.157 mm$

part b)

$k = \frac{\omega}{v}$

here we know that

$\omega = 2\pi f$

$\omega = 2\pi(92.2) = 579.3 rad/s$

so we have

$k = \frac{579.3}{5.69}$

$k = 101.8 rad/m$

Part c)

$\omega = 579.3 rad/s$

Part d)

here since wave is moving in negative direction so the sign of $\omega$ must be positive

4 0

4 years ago

A tornado warning means that the current weather conditions could produce a tornado. True or False

WARRIOR [948]

true because it means that the cloud formation of a tornado has been already spotted.

4 0

3 years ago

Read 2 more answers