1) The current in a light bulb is 0.335 Amps. How long does it take for a total charge of 2.76 C to

A balloon is filled with helium at a pressure of 2.4 x 105 Pa. The balloon is at a

garri49 [273]

1)
p = 2.4 * 10^5 Pa
T = 18° C + 273.15 = 291.15 k
r = 0.25 m => V = [4/3]π(r^3) = [4/3]π(0.25m)^3 = 0.06545 m^3 = 65.45 L

Use ideal gas equation: pV = nRT => n = pV / RT = [2.4*10^5 Pa * 0.06545 m^3] / [8.31 J/k*mol * 291.15k] = 6.492 mol

Avogadro number = 1 mol = 6.022 * 10^23 atoms

Number of atoms = 6.492 mol * 6.022 *10^23 atom/mol = 39.097 * 10^23 atoms = 3.91 * 10^24 atoms

2) Double atoms => double volume

V2 / V1 = r2 ^3 / r1/3

2 = r2 ^3 / r1 ^3 => r2 ^3 = 2* r1 ^3

r2 = [∛2]r1

The factor is ∛2

5 0

3 years ago

You go to the hardware store to buy a new 50 ft garden hose. You find you can choose between hoses of ½ inch and 5/8 inch inner

omeli [17]

To solve this problem it is necessary to consider two concepts. The first of these is the flow rate that can be defined as the volumetric quantity that a channel travels in a given time. The flow rate can also be calculated from the Area and speed, that is,

Q = V*A

Where,

A= Cross-sectional Area

V = Velocity

The second concept related to the calculation of this problem is continuity, which is defined as the proportion that exists between the input channel and the output channel. It is understood as well as the geometric section of entry and exit, defined as,

$Q_1 = Q_2$

$V_1A_1=V_2A_2$

Our values are given as,

$A_1=\frac{1}{2}^2*\pi=0.785 in^2$

$A_2=\frac{5}{8}^2*\pi=1.227 in^2$

Re-arrange the equation to find the first ratio of rates we have:

$\frac{V_1}{V_2}=\frac{A_2}{A_1}$

$\frac{V_1}{V_2}=\frac{1.227}{0.785}$

$\frac{V_1}{V_2}=1.56$

The second ratio of rates is

$\frac{V2}{V1}=\frac{A_1}{A2}$

$\frac{V2}{V1}=\frac{0.785}{1.227}$

$\frac{V2}{V1}=0.640$

3 0

3 years ago

If two objects at different temperatures are in contact with each other, what happens to their temperatures?

miv72 [106K]

In that case, heat energy flows from the warmer object to the cooler one.
As heat flows from one to the other, the temperature of the warmer object
falls, and the temperature of the cooler object rises. When the temperatures
are equal, the flow of heat energy from one to the other stops.

6 0

2 years ago

19. Calculate the work done when a 30 N force pushes a rock 10 m. a) 3J b) 0.33 J c) 40 J d) 300 J

aksik [14]

19. Calculate the work done when a 30 N force pushes a rock 10 m. a) 3J b) 0.33 J c) 40 J d) 300 J

20. How far did a rock move if a force of 200 N moved it doing 100 J of work? a) 2 m b) 0.5 m c) 20,000 m d) 300 m

21. An explosion of gas from a Hawaiian volcano blows a rock into the sky. the rock has 2000J of kinetic energy. What was its mass if the rock had a velocity of 20m/s. a) 200Kg b) 20,000Kg c) 10Kg d) 200Kg

22. How much potential energy does a 2 kg book have if it is 2 meters from the ground? a) 39.2J b) 12 J c) 19.6 J d) 98 J

23. 45J of work were done on the object that moved 5M. How much force was applied to the object? a) 8N b) 9N c) 225N d) ON

24. If you do 40 joules of work lifting a 10N box, how high is the shelf you move it to. a) 400m b) 50m c) 40m d) 4m

25. A force of 100 newtons was necessary to lift a rock. A total of 150 joules of work was done. How far was the rock lifted? a) 1.5 m b) 15 m c) 0.15 m d) 150 m19. Calculate the work done when a 30 N force pushes a rock 10 m. a) 3J b) 0.33 J c) 40 J d) 300 J