Answer:
(D) Vega must produce more energy than HR 4374.
Explanation:
The apparent visual magnitude is defined as the luminosity of a star seen from earth. The Greek astronomer Hipparcos was the first who invent a numerical scale to describe how bright a star appear to be in the sky to the naked eye, so he gave an apparent magnitude of 6 to the faintest star in the sky and an apparent magnitude of 1 to the brigthest one. Since the arrive of the telescope era this range was expanded to negative numbers for the most luminous one.
The human eye has a logaritmical response to the luminosity of stars, so as an example, if one star has an apparent magnitude of 6 and another one has an apparent magnitude of 1, the second one will be 100 times brigther than the first one. In the other hand, for a star that has apparent magnitude of 1 it will appear to be 2.512 times brigther than a star with apparent magnitude of 2.
The apparent magnitude of a star can variate as a consecuence of the distance from earth or for its energy production.
With all these facts clear enough described above, it is easier to conclude that as the two star are at the same distance the apparent visual magnitude will depend in the energy production. In the case of Vega it has an apparent visual magnitude of 0.03, while HR 4374 has an apparent visual magnitude of 4.87. According with the scale stablished for Hipparcos, Vega will be more luminous than HR 4374. This means that Vega produce more energy than HR 4374.
Explanation:
It is given that,
Initial speed of a golfer, u = 29 m/s
If it travels the maximum possible distance before landing. It means that it is projected at an angle of 45 degrees.
(a) We need to find the time spent by the ball in the air. It can be calculated by using second equation of motion.
Here,
a = -g
s = 0 (it is displacement and it is equal to 0 as the ball lands on the green).
So,
So, it will take 4.184 seconds in the air.
(b) let x is the longest hole in one that the golfer can make if the ball does not roll when it hits the green. It can be given by :
Hence, this is the required solution.
Answer:
Explanation:
When the rock is immersed in unknown liquid the forces that act on it are shown as under
1) Tension T by the string
2) Weight W of the rock
3) Force of buoyancy due to displaced liquid B
For equilibrium we have 
=
When the rock is suspended in air for equilibrium we have
When the rock is suspended in water for equilibrium we have
+ 
=
Using the given values of tension and solving α,β,γ simultaneously for 
we get
Solving for density of liquid we get
Force = rate of change of momentum = 0.16(38 + 44)/0.002 = 6560 N
We know, Potential Energy = m * g * h
Here, mass & gravity would be same, but their height will change so it will be:
ΔU = U₂ - U₁
ΔU = mgh₂ - mgh₁
ΔU = mg (h₂ - h₁)
Hope this helps!
