Which material is ideal for an office door that allows light to pass through, but maintains privacy?

Determined to test the law of gravity for himself, a student walks off a skyscraper 180 m high, stopwatch in hand, and starts hi

Sati [7]

Answer:

a) v₀ = - 164.62 m / s , c) y = 122.5 m

Explanation:

We can solve this exercise using the free fall kinematic relations.

We put our reference system on the floor, so the height of the skyscraper is y₀ = 180m and the floor level is y = 0 m

For the boy

y = y₀ + v₀ t - ½ g t²

with free fall its initial speed is zero

y = ½ g t2

For superman

y = y₀ + v₀ (t-5) - ½ g (t-5)²

how superman grabs the lot just before hitting the ground

we look for the time it takes the boy down

t = √ (2 y₀ / g)

t = √ (2 180 / 9,8)

t = 6.06 s

in the equation for superman, we clear the volume and calculate

v₀ (t-5) = -y₀ + ½ g (t-5)²

v₀ (6.06 -5) = -180 + ½ 9.8 (6.06 -5)²

v₀ 1.06 = -174.49

v₀ = - 174.49 / 1.06

v₀ = - 164.62 m / s

the negative sign indicates that the initial speed is down

b) to graph the position of the two we use the table

t (s) Y_boy (m) Y_superman (m)

0 180 180

1 175.1 180

5 57.5 180

6 3.6 10.18

see attachment for the two curves

c) calculate the height that falls a lot in the 5 seconds (t = 5)

y = -1/2 g t²

y = ½ 9.8 5²

y = 122.5 m

for this height superman has not yet left the skyscraper, so the boy hits the ground

8 0

4 years ago

A pneumatic system consists of several identical 1.5 inch diameter cylinders to lift 450-pound pallets in a warehouse. the gauge

DerKrebs [107]

The applicable equation:

P = F/A

P = pressure
F = Force or weight
A = surface area

Pressure on each cylinder = (W/n)/A
Where n = number of cylinders. Additionally, pressure in the reservoir is equivalent to the pressure in each cylinder.
Net pressure = 75 - 14.7 = 60.3 psi

Therefore,
60.3 = (W/n)/A = (450/n)/(πD^2/4) = (450/n)/(π*1.5^2/4) = (450/n)/(1.7671)
60.3*1.7671 = 450/n
106.03 = 450/n
n = 450/106.3 = 4.244 ≈ 5

The number of cylinders is 5.

3 0

3 years ago

What is the position of the earth, moon, and sun during a new moon?

svetlana [45]

The Moon always rotates about the Earth in its orbit. The position of the Earth, moon and sun during a new moon is Earth is in between Sun and Moon.

When moon has travelled for 14 days, it starts its journey again for the next 14 days. The journey starts from the new moon to the full moon. The position of new and full moon is the same. At this time, the Earth is in between the Sun and the Moon.

Thus, the position of the Earth, moon and sun during a new moon is Earth is in between Sun and Moon.

Learn more about New Moon.

brainly.com/question/13538936

#SPJ2.

8 0

2 years ago

Read 2 more answers

list the steps involved in using nuclear fission to generate electricity. begin with the role of the fuel rods

adoni [48]

When an atom of nuclear<span> fuel (uranium) absorbs a neutron, the uranium will </span>fission into two smaller atoms (waste) and release one to three neutrons. The kinetic energy of the waste is used to heat the water for the steam turbine. The neutrons are used to fission<span> the next lot of uranium atoms and the process continues.</span>

3 0

3 years ago

Read 2 more answers

A 26.3 kg object is traveling at 21.0 m/s north. What average net force is required to bring this object to a stop in 2.60 secon

taurus [48]

The average force is -212.4 N

Explanation:

We can solve this problem by using the impulse theorem, which states that the impulse exerted on the object (the product of the force exerted and the time) is equal to the change in momentum of the object:

$F \Delta t = m \Delta v$