Answer:
34 m/s
Explanation:
Potential energy at top = kinetic energy at bottom + work done by friction
PE = KE + W
mgh = ½ mv² + Fd
mg (d sin θ) = ½ mv² + Fd
Solving for v:
½ mv² = mg (d sin θ) − Fd
mv² = 2mg (d sin θ) − 2Fd
v² = 2g (d sin θ) − 2Fd/m
v = √(2g (d sin θ) − 2Fd/m)
Given g = 9.8 m/s², d = 150 m, θ = 28°, F = 50 N, and m = 65 kg:
v = √(2 (9.8 m/s²) (150 m sin 28°) − 2 (50 N) (150 m) / (65 kg))
v = 33.9 m/s
Rounded to two significant figures, her velocity at the bottom of the hill is 34 m/s.
Answer:
(A) 1.43secs
(B) -2.50m/s^2
Explanation:
A commuter backs her car out of her garage with an acceleration of 1.40m/s^2
(A) When the speed is 2.00m/s then, the time can be calculated as follows
t= Vf-Vo/a
The values given are a= 1.40m/s^2 , Vf= 2.00m/s, Vo= 0
= 2.00-0/1.40
= 2.00/1.40
= 1.43secs
(B) The deceleration when the time is 0.800secs can be calculated as follows
a= Vf-Vo/t
= 0-2.00/0.800
= -2.00/0.800
= -2.50m/s^2
Answer:
Option d
The minimum angular separation between two objects that the Hubble Space Telescope can resolve is 
.
Explanation:
The resulting image in a telescope that will be gotten from an object is a diffraction pattern instead of a perfect point (point spread function (PSF)).
That diffraction pattern is gotten because the light encounters different obstacles on its path inside the telescope (interacts with the walls and edges of the instrument).
The diffraction pattern is composed by a central disk, called Airy disk, and diffraction rings.
The angular resolution is defined as the minimal separation at which two sources can be resolved one for another, or in other words, when the distance between the two diffraction pattern maxima is greater than the radius of the Airy disk.
The angular resolution can be determined in analytical way by means of the Rayleigh criterion.
(1)
Where 
is the wavelength and D is the diameter of the telescope.
Notice that it is necessary to express the wavelength in the same units than the diameter.
⇒ 
Finally, equation 1 can be used.
Hence, the minimum angular separation between two objects that the Hubble Space Telescope can resolve is .
1. The velocity of the spacecraft at position 2 is greater than the velocity of the craft at position 4.
This is due the gravity field of the Earth is used to accelerate the craft. This is true when in a specific point the direction of the movement of the craft is the same direction of the movement of the planet.
In this case the craft will be “catched” by the Earth’s gravitational field, making the craft to enter a circular orbit.
2. At point 1, the direction of the spacecraft changes because of the gravitational force between earth and the spacecraft.
As explained in the first answer, this is the exact point where the trajectory of the spacecraft enters into a circular orbit because of the attraction due gravity of the Earth and therefore changes its direction.
3. Position 3 represents the orbital path of Earth
Being this the orbital path of the Earth and considering the trajectory of the craft, the condition of accelerating the craft is accomplished. If the orbital path of the Earth were the opposite, the effect on the craft would be braking.
Note all of these is related to the gravitational assistance, this consists in a maneuver in which the energy of the gravitational field of a planet or satellite is used to obtain an acceleration or braking of the probe or craft, changing its trajectory.
To learn more about velocity of the spacecraft : brainly.com/question/11900446
#SPJ4
Answer:
The chemical compounds of living things are known as organic compounds because of their association with organisms and because they are carbon-containing compounds. Organic compunds, which are the compounds associated with life processes, are the subject matter of organic chemistry.
Explanation:
