Question 7 (2 points)

A car of weight 300N moved through a distance of 10m when pushed by 3 students

Sati [7]

The work done by the three students is 3,000 J.

The energy transferred in the process is 3,000 J.

Work done is the product of force and distance moved by the object.

W = Fd

The work done by the three students is calculated as follows;

W = 300 x 10

W = 3,000 J

<h3>What is energy transfer?</h3>

This is means by which energy is converted from one form to another.

The energy transferred in the process is determined by work energy theorem.

E = W

E = 3,000 J

Learn more about work-energy theorem here: brainly.com/question/22236101

3 0

2 years ago

The total negative charge on the electrons in 1mol of helium (atomic number 2, molar mass 4) is ________?

DaniilM [7]

Answer:

$1.92\times 10^5 C$

Explanation:

We are given that

Atomic number=2

We have to find the total negative charge on the electrons in one mole of Helium.

We know that atomic number=Proton number

Proton number=Number of electrons=2

Number of electrons in Helium=2

1 mole of Helium= $6.02\times 10^{23}$ atoms

We know that q=ne

Where n =Number of fundamental units

e=Charge on electron

1 e= $1.6\times 10^{-19}C$

Using the formula

$q=2\times 1.6\times 10^{-19}=3.2\times 10^{-19}C$

Total negative charge in 1 mole= $3.2\times 10^{-19}\times 6.02\times 10^{23}=1.92\times 10^5C$

Hence, the total negative charge on the electrons in 1 mole of Helium= $1.92\times 10^5 C$

4 0

3 years ago

If the humidity in a room of volume 410 m3 at 25 ∘C is 70%, what mass of water can still evaporate from an open pan? Express you

Keith_Richards [23]

Answer:

$m=1864.68\ g$

Explanation:

Given:

volume of air in the room, $V=410\ m^3$

temperature of the room, $T=25+273=298\ K$

<u>Saturation water vapor pressure at any temperature T K is given as:</u>

<u /> $p_{sw}=\frac{e^{(77.3450 + 0.0057\times T - \frac{ 7235}{T} )}}{T^{8.2}}$ <u />

putting T=298 K we have

$p_{sw}=3130\ Pa$

<u>The no. of moles of water molecules that this volume of air can hold is:</u>

Using Ideal gas law,

$P.V=n.R.T$

$n=\frac{P_{sw}.V}{R.T}$

$n=\frac{3130\times 410}{8.314\times 298}$

$n=518\ moles$ is the maximum capacity of the given volume of air to hold the moisture.

Currently we have 80% of n, so the mass of 20% of n:

$m=(20\%\ of\ n)\times M}$

where;

M= molecular mass of water

$m=0.2\times 518\times 18$

$m=1864.68\ g$ is the mass of water that can vaporize further.

3 0

3 years ago

a 0.15 kg baseball has a momentum of 0.78 kg*m/s just before it lands on the ground. What was the ball's speed just before landi

vovangra [49]

5.2m/s

Explanation:

Given parameters:

Mass of baseball = 0.15kg

Momentum of baseball = 0.78kgm/s

Unknown:

Speed of baseball = ?

Solution:

The momentum of the baseball is a function of the product of the mass and velocity. It is a vector quantity:

Momentum = mass x velocity

Since the speed of the ball is unknown:

Velocity = $\frac{momentum }{mass}$

= $\frac{0.78}{0.15}$

= 5.2m/s

The speed of the baseball before it lands is 5.2m/s

Learn more:

Momentum brainly.com/question/9484203

#learnwithBrainly

4 0

3 years ago

The impulse given to a ball with massb of 2kg is 16 Ns. if the ball starts grin the rest, what is its final velocity?

Ainat [17]

B because it will not be any thing else

6 0

3 years ago