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2 years ago

The power of a motor is 60kW. At what speed can it raise a load of 50000

1 answer:

8 0

Well right off the bat, you've handed us a serious problem. You left the unit off of the 50,000, so we don't know the single most important thing that we need to know about the load.

Is the load 50,000 kilograms ? 50,000 Newtons ? 50,000 pounds ? Each of these will have a different answer.

Since you didn't specify the unit, I can make it anything I want, and I can pick the unit to make the problem easy to solve.

So I'm going to say that the load weighs 50,000 Newtons, and now I shall proceed to solve the problem that I have invented.

If you're using a motor that's marked "60 kW", that number is the maximum safe power the motor can deliver without overheating and breaking down. In order to raise our 50,000N load as fast as possible, we'll run the motor at its maximum rated power of 60 kW. That means it'll do 60,000 Joules of work for us every second.

Power = 60,000 Joules/second

Power = 60,000 Newton-meters/second

60,000 Newton-meters/sec = (50,000 Newton) x S meters/sec.

Divide each side by 50,000 Newtons:

S = (60,000 Newton-m/sec) / (50,000 Newton)

S = (60,000/50,000) meter/sec

Speed = 1.2 meters/sec

Our 60 kW motor can raise the load at the speed of 1.2 m/s or any slower, but no faster than that.

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Explain why the atomic mass of an element is weighted average mass

madreJ [45]

Explanation:

The mass written on the periodic table is an average atomic mass taken from all known isotopes of an element. This average is a weighted average, meaning the isotope's relative abundance changes its impact on the final average. The reason this is done is because there is no set mass for an element.

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2 years ago

A ball is dropped from rest from a high window of a tall building and falls for 4 seconds. Neglecting air resistance, the final

Semenov [28]

Answer:

The final velocity of the ball is 39.2 m/s.

Explanation:

Given that,

A ball is dropped from rest from a high window of a tall building.

Time = 4 sec

We need to calculate the final velocity of the ball

Using equation if motion

$v=u+gt$

Where, v = final velocity

u = initial velocity

g = acceleration due to gravity

t = time

Put the value into the formula

$v=0+9.8\times4$

$v=39.2\ m/s$

Hence, The final velocity of the ball is 39.2 m/s.

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3 years ago

A centrifugal pump is operating at a flow rate of 1 m3/s and a head of 20 m. If the specific weight of water is 9800 N/m3 and th

tamaranim1 [39]

Answer:

The power required by the pump is nearly 230.588 kW

Explanation:

Flow rate of the pump Q = 1 m^3/s

the head flow H = 20 m

specific weight of water γ = 9800 N/m^3

efficiency of the pump η = 85%

First note that specific gravity of water is the product of the density of water and acceleration due to gravity.

γ = ρg

where ρ is density. For water its value is 1000 kg/m^3

g is the acceleration due to gravity = 9.81 m/s^2

The power to lift this water at this rate will be gotten from the equation

P = ρgQH

but ρg = γ

therefore,

P = γQH

imputing values, we'll have

P = 9800 x 1 x 20 = 196000 W

But the centrifugal pump that will be used will only be able to lift this amount of water after the efficiency factor has been considered. The power of pump needed must be greater than this power.

we can say that

196000 W is 85% of the power of the pump power needed, therefore

196000 = 85% of $P_{p}$

where $P_{p}$ is the power of the pump needed

85% = 0.85

196000 = 0.85 $P_{p}$

$P_{p}$ = 196000/0.85 = 230588.24 W

Pump power = 230.588 kW

3 0

3 years ago

A calorimeter contained 350.0 g of water [cp=4.18 J/(g °C)] at 24.0 °C. An electric current was passed through a heater placed i

Shtirlitz [24]

Cp shows the amount of energy needed to raise temperature by one degree for one gram of water.

Formula for calculating cp is:
$cp= \frac{energy}{(mass)*( temperature_{change} ))} \\ temperature_{change}= \frac{energy}{(mass)*( cp))} \\ \\ temperature_{change}= \frac{16700}{(350)*( 4.18))} \\ \\ temperature_{change}=2.73 \\ \\ temperature_{final} =temperature_{initial}+temperature_{change} \\ temperature_{final}=24 + 2.73 \\ temperature_{final}=26.73$

Final temperature is 26.73°C.

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3 years ago

How do you change the thermos into an open energy system

kvasek [131]

To change the thermos into an open energy system, take off the the cap

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3 years ago