Interstellar gas clouds are common in many galaxy, like the Orion nebulae which many young stars are being born. A typical nebula is many light years in diameter and contains enough material mass to make several thousand stars the size of our sun. The majority of the gas in nebulae consist of molecules of hydrogen and helium-but most nebulae also contain atoms of other elements. All known element in our periodic table is also being made inside this crucible of this immense hot gas. The source of the organic molecules is still a mystery. Irregularities in the density of the gas causes a net gravitational force that pull the gas molecules close together.
Answer:
W = 34.64 ft-lbs
Explanation:
given,
Horizontal force = 4 lb
distance of push, d = 10 ft
angle of ramp, θ = 30°
Work done on the box = ?
We know,
W = F.d cos θ
W = 4 x 10 x cos 30°
W = 40 x 0.8660
W = 34.64 ft-lbs
Hence, work done on the box is equal to W = 34.64 ft-lbs
Answer: option (D.)They send signals in the gigahertz range to relays in the line of sight.
Explanation:
Microwaves are a form of electromagnetic waves with wavelengths between from about a meter to a millimeter; and they possess frequencies between 300 mega hertz(MHz )and 300 giga hertz(GHz.)
Microwaves travel by line-of-sight; unlike other radio waves of lower frequency. They do not bend around hills, nor follow the earth's surface as ground waves, nor reflect from the ionosphere .Therefore land microwave communication links are restricted only tovisual horizon to about 40 miles (64 km).
First of all, how long does it take it to fall 0.93m to the floor ?
Distance falling from rest = (1/2) · (g) · (T²) <== memorize this formula
(0.93 m) = (1/2) (9.8m/s²) (T²)
Divide each side by (4.9 m/s²) : T² = (0.93/4.9) = 0.1898 s²
Square root each side: T to hit the floor = 0.436 second
It got 0.56m away from the desk horizontally in 0.436 sec.
Speed = (distance) / (time) <=== memorize this formula
Speed = (0.56 m) / (0.436 sec)
<em>Speed = 1.28 m/s</em>
Explanation:
<h2>Answer:-</h2>
The Object was at rest. So, Initial Velocity is Zero.
- [Initial Velocity]u = 0
- [Final Velocity]v = 20 m/s
- [Time]t = 2 seconds
- Mass = 4kg
- Force = ?
We know that:-
Applying it, we get:-
Hope it helps :)