All categories

4 years ago

Plz help asap

Physics

1 answer:

Ierofanga [76]4 years ago

4 0

1. a mineral is a solid inorganic substance of natural occurrence
2. igneous, metamorphic and sedimentary

You might be interested in

In a circuit, three pieces of wire labeled A, B and C are joined at a common point, D. If wire B carries 1.5 mA in a direction a

Alex_Xolod [135]

Answer:

correct option is a. 0.2 mA toward D

Explanation:

given data

B carries = 1.5 mA

C carries current = 1.3 mA

solution

we take positive direction of current going away from the point D

and negative direction of current coming towards point D

so we use here kirchoff's current law that is

iA + iB + iC = 0 ......................1

iA + 1.5 + (-1.3) = 0

iA = - 0.2 mA

so that current in wire A is 0.2 mA towards point D

correct option is a. 0.2 mA toward D

7 0

3 years ago

A fire truck emits an 880Hz siren. As the truck approaches an observer on the sidewalk, he perceives the pitch to be 950Hz. Appr

Ludmilka [50]

Answer:

The pitch that he hears after the truck passes and is moving away is 819.6 Hz.

Explanation:

The pitch that he hears after the truck passes and is moving away can be calculated using the following equation:

$f = f_{0}*\frac{v_{s} \pm v_{o}}{v_{s} \pm v_{f}}$

Where:

$f$ : is the perceived frequency

$f_{0}$ : is the emitted frequency

$v_{s}$ : is the speed of sound = 340 m/s

$v_{o}$ : is the speed of the observer = 0 (he is not moving)

$v_{f}$ : is the speed of the fire truck

First, we need to find the speed of the fire truck. When it approaches the observer we have:

$f = f_{0}*\frac{v_{s} + v_{o}}{v_{s} - v_{f}}$

$950 Hz = 880 Hz*\frac{340 m/s}{340 m/s - v_{f}}$

$v_{f} = 340 m/s - \frac{880 Hz*340 m/s}{950 Hz}$

$v_{f} = 25.05 m/s$

Hence, the speed of the fire truck is 25.05 m/s.

Now, we can calculate the pitch that the observer hears after the truck passes:

$f = f_{0}*\frac{v_{s} - v_{o}}{v_{s} + v_{f}}$

$f = 880 Hz*\frac{340 m/s}{340 m/s + 25.05 m/s}$

$f = 819.6 Hz$

Therefore, the pitch that he hears after the truck passes and is moving away is 819.6 Hz.

I hope it helps you!

7 0

3 years ago

You cool a 130.0 g slug of red-hot iron (temperature 745 ∘C) by dropping it into an insulated cup of negligible mass containing

erik [133]

Answer:

A) 100°C

B) 211 g

Explanation:

Heat released by red hot iron to cool to 100°C = 130 x .45 x 645 [ specific heat of iron is .45 J /g/K]

= 37732.5 J

heat required by water to heat up to 100 °C = 85 x 4.2 x 80 = 28560 J

As this heat is less than the heat supplied by iron so equilibrium temperature will be 100 ° C. Let m g of water is vaporized in the process . Heat required for vaporization = m x 540x4.2 = 2268m J

Heat required to warm the water of 85 g to 100 °C = 85X4.2 X 80 = 28560 J

heat lost = heat gained

37732.5 = 28560 + 2268m

m = 4 g.

So 4 g of water will be vaporized and remaining 81 g of water and 130 g of iron that is total of 211 g will be in the cup . final temp of water will be 100 °C.

3 0

3 years ago

an ideal gas system undergoes an adiabatic process in which it expands and does 20 J of work on its environment. how much energy

ehidna [41]

Answer:

Zero.

Explanation:

An adiabatic process is one in which there is no exchange of heat energy. Therefore, in an adiabatic process, heat is neither added to the system not it is removed from the system.

The work done by the gas on the environment is 20 J. This energy is equal to the change in internal energy for an adiabatic process.

Therefore, for an ideal gas to undergo an adiabatic process in which it expands and does 20 J of work on its environment, the heat exchange is zero.

8 0

3 years ago

Ramon is playing soccer. The ball comes straight at him, and he kicks it to a player on his right. His kick is an example of

monitta

I believe your answer is d).

Hope you find this helpful! :)

7 0

4 years ago

Read 2 more answers