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2 years ago

How much force is required to accelerate a 12 kg mass at 5 m/s 2

Physics

1 answer:

Savatey [412]2 years ago

4 0

Answer:

60 N

Explanation:

This is just Newton's Second Law

F = m*a

F = ?

m = 12 kg

a = 5 m/^2

F = 5*12 = 60 Newtons

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How many types air I need a formula of calculating the s i unti of force

yKpoI14uk [10]

The si unit of force is newton.

so, F is eqal to m*g

4 0

3 years ago

Read 2 more answers

A 2.64-kg copper part, initially at 400 K, is plunged into a tank containing 4 kg of liquid water, initially at 300 K. The coppe

marin [14]

Answer:

a) $T_f=305.7049\ K$

b) $\Delta S=313.51\ J.K^{-1}$

Explanation:

Given:

mass of copper, $m_c=2.64\ kg$

initial temperature of copper, $T_{ic}=400\ K$

specific heat capacity of copper, $c_c=385\ J.kg^{-1}.K^{-1}$

mass of water, $m_w=4\ kg$

initial temperature of water, $T_{iw}=300\ K$

specific heat capacity of water, $c_w=4200\ J.kg^{-1}.K^{-1}$

∵No heat is lost in the environment and the heat is transferred only between the two bodies:

Heat rejected by the copper = heat absorbed by the water

$2.64\times 385\times (400-T_f)= 4\times 4200\times (T_f-300)$

$T_f=305.7049\ K$

Now the amount of heat transfer:

$Q=m_c.c_c.(T_{ic}-T_{f})$

$Q=2.64\times 385\times (400-305.7049)$

$Q=95841.5841\ J$

∴Entropy change

$\Delta S=\frac{dQ}{T}$

$\Delta S=\frac{95841.5841}{305.7049}$

$\Delta S=313.51\ J.K^{-1}$

5 0

4 years ago

Isaac walks 4 blocks north. Then he turns around and walks 1 block south.

kramer

Answer:

Isaac walked a distance of 5 blocks, and his displacement was 3 blocks north.

Explanation:

Distance is what he covered from the beginning, while displacement was what he covered in a specific direction

7 0

3 years ago

If it has enough kinetic energy, a molecule at the surface of the Earth can "escape the Earth's gravitation", in the sense that

user100 [1]

Answer:

$K_E=mgr_E$

Explanation:

By conservation of energy, the sum of the kinetic and gravitational potential energies at the surface of the Earth must be equal than their sum at infinity, so we have:

$K_E+U_E=K_\infty+U_\infty$

$\frac{mv_E^2}{2}-\frac{GM_Em}{r_E}=\frac{mv_\infty^2}{2}-\frac{GM_Em}{r_\infty}$

Where $G=6.67\times10^{-11}Nm^2/kg^2$ is the gravitational constant, $M_E=5.97\times10^{24}kg$ and $r_E=6371000m$ are the mass and radius of the Earth, m is the mass of the particle, $v_E$ its velocity at the surface of the Earth (which would be its escape velocity) and $v_\infty$ and $r_\infty$ are the velocities and distance at infinity, which would be null and infinity respectively, so the right hand side of our equation is 0J, which leaves us with:

$\frac{GM_Em}{r_E}=\frac{mv_E^2}{2}=K_E$

Also, since the force the molecule experiments is the force of gravity (disregarding drag), we can write its weight in terms of Newton's Law of Gravitation:

$F=mg=\frac{GM_Em}{r_E^2}$

Which means that:

$\frac{GM_Em}{r_E}=mgr_E$

So finally putting all together we can write:

$K_E=\frac{GM_Em}{r_E}=mgr_E$

4 0

3 years ago

Which most likely indicate a chemical change has occurred ?

Allushta [10]

If a new substance suddenly appears that wasn't there originally,
then a chemical change has occurred.

Like for example, (this is the only example I can think of right now):

-- You leave your bicycle outside in the rain, and it gets wet, and
a few days later there's some rust on it.

-- You scrape off some of the rust, take it to school, give it to the
Chemistry teacher, and ask her to analyze it and tell you what it
is. Later that day, she tells you it's a substance called "Iron oxide".

-- Where did that come from ? There was no iron oxide there.
There was only iron in the bicycle, and air, and water.

-- The iron oxide formed from a chemical change when the iron
on the surface of the bike combined with some of the oxygen in
the air, and molecules of a new substance were created. (For
some reason, the presence of water makes this chemical reaction
go faster.)

5 0

3 years ago