Answer:
Velocity of a proton, 
Explanation:
It is given that,
Potential difference, 
Let v is the velocity of a proton that has been accelerated by a potential difference of 15 kV.
Using the conservation of energy as :
q is the charge of proton
m is the mass of proton
or
So, the velocity of a proton is 
. Hence, this is the required solution.
When an opaque obstacle is placed between a source of light and a screen, a shadow of the obstacle is formed on the screen. The kind of shadow depends on the size of the source of light. In other words, the earth casts its shadow on the moon. The solar eclipse occurs when the moon comes between the sun and the earth.
You didn't mention it, but the trumpeter herself has to be standing still.
<span>Person C, the one running towards the trumpeter, hears a pitch
that is higher than B-flat. (A)
Person B, the one running away from the trumpeter, hears a pitch
that is lower than B-flat.
Person D, the one standing still the whole time, hears the B-flat.</span>
