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3 years ago

Kiran runs along a straight road of length 150 m. After

Physics

1 answer:

Alexandra [31]3 years ago

4 0

Answer:

Explanation:

Speed and velocity are not the same thing, as I'm sure you have determined while in physics. To find the average speed, we add the total distance run by Kiran and divide that total number of meters by the number of seconds it took to do this (just because I am going to state the speed and velocity in terms of m/s as opposed to m/min). To find the average velocity, we add the displacements together and divide by the total time. First the average speed:

$s=\frac{150+150}{60}=\frac{300}{60}=5\frac{m}{s}$

Velocity has direction. If Kiran runs to the end of the road (which we will call positive) and then runs back to the start (that direction will be negative), then his displacement fits into the velocity equation as

$v=\frac{150+(-150)}{60}=0$ That means, even though he ran a lot and I'm sure he was very tired, his average velocity for the trip was 0 m/s. When velocity is 0, remember that that means that the total displacement was 0.

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Which object had more potential energy when it was lifted to a distance of 1000 centimeters? Show your calculation.

RSB [31]

Explanation:

We Know That

POTENTIAL ENERGY= MASS*g*HEIGHT

When the objects are lifted to same height then the object with heavier mass would have the highest potential energy

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2 years ago

An 800-g block of ice at 0.00°C is resting in a large bath of water at 0.00°C insulated from the environment. After an entropy c

Allisa [31]

Answer:

Unmeltedd ice = 308.109 g

Explanation:

Gibbs Free energy:

A systems Gibbs Free Energy is defined as the free energy of the product of the absolute temperature and the entropy change less than the enthalpy change.

Therefore, G = ΔH-TΔS

where G is Gibbs Free Energy

ΔH is enthalpy change

T is absolute temperature

ΔS is entropy change

Here since there is a phase change, therefore G will be 0.

∴ΔH = TΔS

Given: Temperature, T = 0°C = 273 K

Entropy change,ΔS = 600 J/K

Latent heat of fusion of water = 333 J/g

∴ΔH = TΔS

∴ΔH = 273 x 600

= 163800 J

So this is the amount of enthalpy that will be used into melting of ice.

∴ΔH = mass of ice melted x latent heat of fusion of water

Mass of ice melted = ΔH / latent heat of fusion of water

= 163800 / 333

= 491.891 g

This is the mass of ice melted.

And initial amount of ice is 800 g

Amount of ice left after melting = Initial amount of ice - amount of ice melted

= 800-491.891

= 308.109 g

Amount of ice remained after melting = 308.109 g

8 0

3 years ago

Even when shut down after a period of normal use, a large commercial nuclear reactor transfers thermal energy at the rate of 150

Phoenix [80]

Answer:

The temperature of the core raises by $2.8^{o}C$ every second.

Explanation:

Since the average specific heat of the reactor core is 0.3349 kJ/kgC

It means that we require 0.3349 kJ of heat to raise the temperature of 1 kg of core material by 1 degree Celsius

Thus reactor core whose mass is $1.60\times 10^{5}kg$ will require

$0.3349\times 1.60\times 10^{5}kJ\\\\=0.53584\times 10^{5}kJ$

energy to raise it's temperature by 1 degree Celsius in 1 second

Hence by the concept of proportionately we can infer 150 MW of power will increase the temperature by

$\frac{150\times 10^{6}}{0.53584\times 10^{8}}=2.8^{o}C/s$

5 0

3 years ago

(1) Explain : Market and its characteristics.

AlekseyPX

Answer:

market is a place where we sell or buy things ( goods)

it's characteristics are

buying and selling goods

perfect competitions

market doesn't refer only a fix place

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3 years ago

A stone is dropped from from rest at the top of a mine shaft. It takes 95 seconds for the stone to fall to the bottom of the min

Marianna [84]

Distance of fall from rest,
without air resistance = (1/2) (gravity) (time)²

   = (1/2) (9.8 m/s²) (95 sec)²

   = (4.9 m/s²) (9,025 sec²)

   = 44,222.5 meters .

The depth of the mine shaft is five times the height of Mt. Everest !

6 0

3 years ago