Answer:
<em>the mass of one helium nucleus should be</em> <em>less than the mass of four hydrogen nuclei.</em>
Explanation:
Deep inside the core of the Sun, enough protons can collide into each other with enough speed that they stick together to form a helium nucleus and generate a tremendous amount of energy at the same time. This process is called nuclear fusion.
The mass-to-energy conversion is described by Einstein's famous equation:
E = mc2, or, in words, energy equals mass times the square of the velocity of light. Because the velocity of light is a very large number, this equation says that lots of energy can be gained from using up a modest amount of mass.
Photons In the proton-proton chain reaction, hydrogen nuclei are converted to helium nuclei through a number of intermediates. The reactions produce high-energy photons (gamma rays) that move through the "radiative layer" surrounding the core. This layer takes up 60 percent of the radius of the Sun. It takes a million years for energy to get through this layer into the "convective layer", because the photons are constantly intercepted, absorbed and re-emitted. In the core, the helium nuclei make up 62% of the mass (the rest is still hydrogen). The radiative and convective layers have about 72% hydrogen, 26% helium, and 2% heavier elements (by mass). The energy produced by fusion is then transported to the solar surface and emitted as light or ejected as high-energy particles.
Answer:
f' = 3665.51 Hz
Explanation:
given,
speed of the hawk = 24.7 m/s
frequency of screech emitted by the hawk = 3400 Hz
speed of sound = 331 m/s
By Doppler's effect

f' is the frequency received by the mouse
v is the speed of the sound
v_s is the speed of the hawk
now,

f' = 1.078 x 3400
f' = 3665.51 Hz
The frequency received by the stationary mouse is equal to 3665.51 Hz
Answer:
The change in momentum is 
Explanation:
From the question we are told that
The time taken for the stone to stop is 
The net force on the rock is 
The impulse of the rock can be mathematically represented as

Substituting values


Now impulse is defined as the rate at which momentum change
Hence the change in momentum
of the rock is equal to the impulse of the rock
So

Answer:
0.98kW
Explanation:
The conservation of energy is given by the following equation,


Where
Mass flow
Specific Enthalpy (IN)
Specific Enthalpy (OUT)
Gravity
Heigth state (In, OUT)
Velocity (In, Out)
Our values are given by,




For this problem we know that as pressure, temperature as velocity remains constant, then


Then we have that our equation now is,



Answer:
D.amplifying sound vibrations from the eardrum
this is correct