Answer:
4. B) 69N
5. B) 7.2kg
Explanation:
Dados los siguientes parámetros;
Masa = 7kg
Peso = 71N
La aceleración debida a la gravedad es igual a 9.8m/s².
a. Para determinar el peso de la siguiente masa;
Matemáticamente, el peso viene dada por la fórmula;
Peso = masa * aceleración debida a la gravedad
Peso = 7 * 9.8
Peso = 68.6 ≈ 69 Newton.
b. ¿Cuál es la masa sobre la tierra de un objeto que pesa.
Peso = masa * aceleración debida a la gravedad
71 = masa * 9.8
Masa = 71/9.8
Masa = 7.2 Kilograms.
Explanation:
Doppler's Effect: If a source is moving towards the observer the frequency of the waves emitted by the source will increase( wavelength will decrease). If the source is moving away from the observer the frequency of the waves emitted by the source will decrease( wavelength will increase). The best example of this is the changing frequency of siren of an ambulance as it moves towards us and then away from us.
The same phenomenon can be observed in celestial objects. When the object will move towards us the wavelength will decrease thus the spectrum will be shifted towards the blue part. This is known as blue shift.
If the object moves away from us the wavelength will increase and thus the spectrum will be shifted towards red part. This is know as Red-shift. This is because red has longer wavelength (620 - 750nm) than blue (450-495nm)
Thus if a galaxy shows us red-shifted spectra it means that it is moving away from us. we have observed this phenomenon in various galaxies thus supporting the expanding universe theory.
Answer:
a) W = 5360 J b) μ = 0.29
Explanation:
a) The work is, bold indicate vectors
W = F. d = F d cos T
W = 40 268 cos 60
W = 5360 J
b) The force of friction and opposes the movement of the body and if the speed of the body is constant implies that the external force in the direction of the movement is equal to the force of friction, or which work is the same
= -5360J
The negative sign is because the force of friction is contrary to the direction of movement
c) Let's write the work of the friction force
= fr d cos 180
fr = μ N
Since the body is on a horizontal surface, from Newton's second law on the Y axis
N-W = 0
N = W
fr = μ W
= - μ W d
μ = -
/ W d
μ = - (-5360) / 69 268
μ = 0.29
<h2>
Answer:
</h2>
The velocity of a satellite describing a circular orbit is <u>constant</u> and defined by the following expression:
(1)
Where:
is the gravity constant
the mass of the massive body around which the satellite is orbiting
the radius of the orbit (measured from the center of the planet to the satellite).
Note this orbital speed, as well as orbital period, does not depend on the mass of the satellite. I<u>t depends on the mass of the massive body.</u>
In addition, this orbital speed is constant because at all times <u>both the kinetic energy and the potential remain constant</u> in a circular (closed) orbit.