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3 years ago

A man performed 500 j of work moving a couch in his living room

Physics

1 answer:

Sergio039 [100]3 years ago

6 0

Incomplete question. Missing part:

"it took him 10 seconds to move the couch. What was his power?"

Answer:

50 W

Explanation:

The power developed is given by:

$P=\frac{W}{t}$

where

W is the work done

t is the time taken

In this problem,

W = 500 J

t = 10.0 s

Substituting into the equation, we find

$P=\frac{500}{10}=50 W$

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You are exploring a distant planet. When your spaceship is in a circular orbit at a distance of 630 km above the planet's surfac

Anarel [89]

Answer:

$R = 24.3 m$

Explanation:

As we know that the orbital speed is given as

$v = \sqrt{\frac{GM}{R + h}}$

here we know that

v = 5500 m/s

$R = 4.48 \times 10^6 m$

$h = 630 km$

now we have

$5500 = \sqrt{\frac{(6.6 \times 10^{-11})M}{4.48 \times 10^6 + 6.30\times 10^5}}$

$M = 2.34 \times 10^24 kg$

now acceleration due to gravity of planet is given as

$a = \frac{GM}{R^2}$

$a = \frac{(6.6 \times 10^{-11})(2.34 \times 10^{24})}{(4.48\times 10^6)^2}$

$a = 7.7 m/s^2$

now range of the projectile on the surface of planet is given as

$R = \frac{v^2 sin2\theta}{g}$

$R = \frac{14.6^2 sin(2\times 30.8)}{7.7}$

$R = 24.3 m$

3 0

3 years ago

A meter stick is held vertically with one end on the floor and is then allowed to fall. Find the speed of the other end when it

Tems11 [23]

Answer:

5.4 ms⁻¹

Explanation:

Here we have to use conservation of energy. Initially when the stick is held vertical, its center of mass is at some height above the ground, hence the stick has some gravitational potential energy. As the stick is allowed to fall, its rotates about one. gravitational potential energy of the stick gets converted into rotational kinetic energy.

$L$ = length of the meter stick = 1 m

$m$ = mass of the meter stick

$w$ = angular speed of the meter stick as it hits the floor

$v$ = speed of the other end of the stick

we know that, linear speed and angular speed are related as

$v = r w\\w = \frac{v}{r}$

$h$ = height of center of mass of meter stick above the floor = $\frac{L}{2} = \frac{1}{2} = 0.5 m$

$I$ = Moment of inertia of the stick about one end

For a stick, momentof inertia about one end has the formula as

$I = \frac{mL^{2} }{3}$

Using conservation of energy

Rotational kinetic energy of the stick = gravitational potential energy

$(0.5) I w^{2} = mgh\\(0.5)(\frac{mL^{2} }{3}) (\frac{v}{L} )^{2} = mgh\\(0.5)(\frac{v^{2} }{3}) = gh\\(0.5)(\frac{v^{2} }{3}) = (9.8)(0.5)\\v = 5.4 ms^{-1}$

7 0

3 years ago

which of these is an example of a biotic factor that could affect the size of a population A-climate b-disease c-a natural disas

andreyandreev [35.5K]

Hey there!

Biotic factors are living organisms. This includes plants, animals, and bacteria. Climate, water, and natural disasters are abiotic factors, which means they are nonliving factors that affect the environment. Disease is caused by bacteria, which is a biotic factor.

Therefore, your answer is B) Disease.

Hope this helps!

4 0

3 years ago

Which is a correct statement of what occurs at a turbine during electricity production?

jarptica [38.1K]

Answer:

The turbine is rotated and rotates the generator to produce electricity.

Explanation:

Within a turbine enters the superheated steam which is at high pressure and high temperature, this steam is previously formed in the boiler when the steam enters the turbine hits each one of the blades of the turbine making it rotate at a given speed, the turbine shaft is coupled to the shaft of an electric generator and thus generates electricity.

It is also important to say that when the steam comes out of the turbine comes out at low pressure, this way the internal operating process is carried out within the turbine.

4 0

3 years ago

Which is an example of a physical change

mote1985 [20]

Water boiling is an example of a physical change. The rest are chemical changes.
Hope that helps!!

6 0

3 years ago