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4 years ago

If element X has 99 protons, how many elctrons does it have?

Physics

2 answers:

slega [8]4 years ago

7 0

It has 99 electrons because an element has the same number of protons and electrons

Art [367]4 years ago

3 0

The same amount. the number of protons is always equal to the number of electrons in a normal state without electric flow. they balance each other out. protons are positive, electrons are negative.

so the number of electrons in this case is 99

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What is dispersion of light?

algol13

Answer:

$\huge \bold \blue{ \underline{ answer}}$

The splitting up of light into its constituent colours while passing from one medium to the other is called dispersion.

3 0

2 years ago

Read 2 more answers

Consider two planets of mass m and 2m,

Rzqust [24]

Answer:

Part a)

$\frac{F_1}{F_2} = 10.125$

Part b)

$\frac{v_1}{v_2} = \sqrt{\frac{4.5r}{r}} = 2.12$

Part c)

$\frac{T_1}{T_2} = 9.54$

Explanation:

Part a)

As we know that the gravitational force is given as

$F = \frac{GMm}{r^2}$

so we will have to find the ratio of force on two planets due to star

so here we have

$\frac{F_1}{F_2} = \frac{m_1r_2^2}{m_2r_1^2}$

$\frac{F_1}{F_2} = \frac{m (4.5r)^2}{(2m) r}$

$\frac{F_1}{F_2} = 10.125$

Part b)

Orbital speed is given as

$v = \sqrt{\frac{GM}{r}}$

so the ratio of two orbital speed is given as

$\frac{v_1}{v_2} = \frac{r_2}{r_1}$

$\frac{v_1}{v_2} = \sqrt{\frac{4.5r}{r}} = 2.12$

Part c)

Time period is given as

$T = 2\pi\sqrt{\frac{r^3}{GM}}$

so the ratio of two time period is given as

$\frac{T_1}{T_2} = \sqrt{\frac{r_1^3}{r_2^3}}$

$\frac{T_1}{T_2} = \sqrt{\frac{4.5r^3}{r^3}}$

$\frac{T_1}{T_2} = 9.54$

8 0

3 years ago

Read 2 more answers

Is it possible for you to take a hike and have the distance you cover be equal to the magnitude of your displacement?

kow [346]

Distance can be equal to displacement ... if the motion is all in a straight line ... but distance can never be greater than displacement.

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4 years ago

A compound is found to have a molar mass of 598 g/mol. if 0.0358 g of the compound is dissolved in enough water to make 175 ml o

zalisa [80]

π=iMRT

Where, π is Osmotic pressure,
i=1 for non-electrolytes,
M is molar concentration of dissolved species (units of mol/L)
R is the ideal gas constant = 0.08206 L atm mol⁻¹K⁻¹,
T is the temperature in Kelvin(K),

Here, to calculate M convert into standard units mg tog, ml to L, c to Kelvin
M= ( $\frac{35.8}{598}$ *10⁻³ )/ 0.175 =(5.987 *10⁻⁵)mol / 0.175L = 34.21*10⁻⁵ mol/L

π=iMRT=(1)*(34.21*10⁻⁵)*(0.08206)*(298.15)=837×10⁻⁵= 8.37×10⁻³ atm
=6.36 torr
(1 atm=760 torr, 1 Kelvin =273.15 °C, 1L=1000ml, 1g=1000mg)

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3 years ago

For the PE formula, why is the height required for calculations? Why do we need to know the height in order to determine PE? *

Fudgin [204]

Answer:

Answer in Explanation

Explanation:

Whenever we talk about the gravitational potential energy, it means the energy stored in a body due to its position in the gravitational field. Now, we know that in the gravitational field the work is only done when the body moves vertically. If the body moves horizontally on the same surface in the Earth's Gravitational Field, then the work done on the body is considered to be zero. Hence, the work done or the energy stored in the object while in the gravitational field is only possible if it moves vertically. This vertical distance is referred to as height. <u>This is the main reason why we require height in the P.E formula and calculations.</u>

The derivation of this formula is as follows:

Work = Force * Displacement

For gravitational potential energy:

Work = P.E

Force = Weight = mg

Displacement = Vertical Displacement = Height = h

Therefore,

P.E = mgh

5 0

3 years ago