What is the mass of a bird if it has a potential energy of 147J when flying at a height of 30 m above the ground?
1 answer:
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Answer:
Force required to accelerate = 794.44 N
Explanation:
Force required = Mass of horse x Acceleration of horse
Mass of horse and rider, m= 572 kg
Acceleration of horse and rider, a = 5 kph per second
Force required = ma
= 572 x 1.39 = 794.44 N
Force required to accelerate = 794.44 N
The electron is accelerated through a potential difference of 
, so the kinetic energy gained by the electron is equal to its variation of electrical potential energy:
where
m is the electron mass
v is the final speed of the electron
e is the electron charge
is the potential difference
Re-arranging this equation, we can find the speed of the electron before entering the magnetic field:
Now the electron enters the magnetic field. The Lorentz force provides the centripetal force that keeps the electron in circular orbit:
where B is the intensity of the magnetic field and r is the orbital radius. Since the radius is r=25 cm=0.25 m, we can re-arrange this equation to find B:
where
m is the electron mass
v is the final speed of the electron
e is the electron charge
Re-arranging this equation, we can find the speed of the electron before entering the magnetic field:
Now the electron enters the magnetic field. The Lorentz force provides the centripetal force that keeps the electron in circular orbit:
where B is the intensity of the magnetic field and r is the orbital radius. Since the radius is r=25 cm=0.25 m, we can re-arrange this equation to find B: