Answer:
A) v₁ = 10.1 m/s t₁= 4.0 s
B) x₂= 17.2 m
C) v₂=7.1 m/s
D) x₂=7.5 m
Explanation:
A)
- Assuming no friction, total mechanical energy must keep constant, so the following is always true:

- Choosing the ground level as our zero reference level, Uf =0.
- Since the child starts from rest, K₀ = 0.
- From (1), ΔU becomes:
- In the same way, ΔK becomes:
- Replacing (2) and (3) in (1), and simplifying, we get:

- In order to find v₁, we need first to find h, the height of the slide.
- From the definition of sine of an angle, taking the slide as a right triangle, we can find the height h, knowing the distance that the child slides down the slope, x₁, as follows:

Replacing (5) in (4) and solving for v₁, we get:

- As this speed is achieved when all the energy is kinetic, i.e. at the bottom of the first slide, this is the answer we were looking for.
- Now, in order to finish A) we need to find the time that the child used to reach to that point, since she started to slide at the its top.
- We can do this in more than one way, but a very simple one is using kinematic equations.
- If we assume that the acceleration is constant (which is true due the child is only accelerated by gravity), we can use the following equation:

- Since v₀ = 0 (the child starts from rest) we can solve for a:

- Since v₀ = 0, applying the definition of acceleration, if we choose t₀=0, we can find t as follows:

B)
- Since we know the initial speed for this part, the acceleration, and the time, we can use the kinematic equation for displacement, as follows:

- Replacing the values of v₁ = 10.1 m/s, t₂= 2.0s and a₂=-1.5m/s2 in (10):

C)
- From (6) and (8), applying the definition for acceleration, we can find the speed of the child whem she started up the second slope, as follows:

D)
- Assuming no friction, all the kinetic energy when she started to go up the second slope, becomes gravitational potential energy when she reaches to the maximum height (her speed becomes zero at that point), so we can write the following equation:

- Replacing from (12) in (13), we can solve for h₂:

- Since we know that the slide makes an angle of 20º with the horizontal, we can find the distance traveled up the slope applying the definition of sine of an angle, as follows:

For a distant astronomical object (a quasar) is moving away from us at half the speed of light, the speed of the light we receive from this quasar is mathematically given as c = 3x108 m/s
<h3>What is the
speed of light?</h3>
Generally, the equation for the is mathematically given as
The speed of light can be said to be measured to be approximately the value c = 3x108 m/s
.
In conclusion, An will not influence 3x108 m/s unless both are inertia and frames refrences where newtons laws are valid, so the speed of light measured from the earth frame is equal to 3x108 m/s
Read more about Speed
brainly.com/question/4931057
You can use the formula:
Work = Force × Distance
W = 100 * (6 - 2)
W = 100 * 4
W = 400 J
hope this helps :)
227kj Because The first thing to do here is to calculate the energy of a single photon of wavelength equal to
527 nm
, then use Avogadro's number to scale this up to the energy of a mole of such photons.
Answer:
95 minutes
Explanation:
According to N.A.S.A, the Hubble Space Telescope makes one orbit around Earth every 95 minutes.
"The Hubble Space Telescope is a large telescope in space. It was launched into orbit by space shuttle Discovery on April 24, 1990. Hubble orbits about 547 kilometers (340 miles) above Earth. It is the length of a large school bus and weighs as much as two adult elephants. Hubble travels about 5 miles per second: That is like traveling from the eastern coast of the United States to the western coast in 10 minutes. Hubble is solar-powered.
Hubble takes sharp pictures of objects in the sky such as planets, stars and galaxies. Hubble has made more than one million observations. These include detailed pictures of the birth and death of stars, galaxies billions of light years away, and comet pieces crashing into Jupiter's atmosphere.
Scientists have learned a lot about the universe from these pictures. Many of them are beautiful to look at."