All categories

3 years ago

What is the speed of a car in meters per second when it is moving at 100km/h?

1 answer:

6 0

You could transfer km to m by * 1000
and hour to second by * 3600
so now 100*1000/3600 = 28 metres per second(approximately)

You might be interested in

Suppose that we use a heater to boil liquid nitrogen (N2 molecules). 4480 J of heat turns 20 g of liquid nitrogen into gas. Note

love history [14]

Answer:

The energy is $9.4\times10^{-21}\ J$

(a) is correct option

Explanation:

Given that,

Energy = 4480 j

Weight of nitrogen = 20 g

Boil temperature = 77 K

Pressure = 1 atm

We need to calculate the internal energy

Using first law of thermodynamics

$Q=\Delta U+W$

$Q=\Delta U+nRT$

Put the value into the formula

$4480=\Delta U+\dfrac{20}{28}\times8.314\times77$

$\Delta U=4480-\dfrac{20}{28}\times8.314\times77$

$\Delta U=4022.73\ J$

We need to calculate the number of molecules in 20 g N₂

Using formula of number of molecules

$N=n\times \text{Avogadro number}$

Put the value into the formula

$N=\dfrac{20}{28}\times6.02\times10^{23}$

$N=4.3\times10^{23}$

We need to calculate the energy

Using formula of energy

$E=\dfrac{\Delta U}{N}$

Put the value into the formula

$E=\dfrac{4022.73}{4.3\times10^{23}}$

$E=9.4\times10^{-21}\ J$

Hence, The energy is $9.4\times10^{-21}\ J$

4 0

3 years ago

Dark matter may explain _____.

Lisa [10]

Dark matter may explain unexpected orbital velocities of stars in galaxies.

4 0

4 years ago

Read 2 more answers

Which event would be impossible to explain by using john dalton’s model of the atom?

Troyanec [42]

Answer: An iron atom emits particles when it is struck by light (by the photoelectric effect)

Explanation:

The first atomic model was the one proposed by Jhon Dalton, according to which it is postulated that:

"Matter is made up of indivisible, indestructible and extremely small particles called atoms."

That is, the atom is a solid and indivisible mass.

However, the fenomenom by which an iron atom emits particles when it is struck by light (known as the photoelectric effect) can not be explaind by this indivisible atom model.

To understand it better:

The photoelectric effect consists of the emission of electrons (electric current) that occurs when light falls on a metal surface under certain conditions.

This is possible by considering light as a stream of photons, where each of them has energy. This energy is be able to pull an electron out of the crystalline lattice of the metal and communicate, in addition, a kinetic energy. This means the atom is not indivisible, but it is a composition of different particles.

In fact, currently it is known that each atom is composed of a nucleus and one or more electrons attached to the nucleus, which is composed of one or more protons and typically a similar number of neutrons.

8 0

3 years ago

Read 2 more answers

In an experiment you are performing, your lab partner has measured the distance a cart has traveled: 28.4inch. You need the dist

weeeeeb [17]

Answer: The multiplication factor is 72.136 cm. This will give you the unit conversion when multiplied with 28.4 inch

Explanation:

1 inch = 2.54 cm

28.4 inches = x cm

Xcm= (28.4 inches × 2.54cm)/1 inch

X= 72.136

6 0

3 years ago

An animal cell placed in pure distilled 100% will

jasenka [17]

in a hypotonic solution like distilled water, a red blood cell would burst, because inside the cell has a higher solute concentration than outside.

In a hypertonic solution, there is a higher solute concentration on the outside of the cell than on the inside, causing the cell to shrivel.

i hope this helps

8 0

3 years ago