Explanation:
a) Power = work / time = force × distance / time
P = Fd/t
P = (85 kg × 9.8 m/s²) (4.6 m) / (12 s)
P ≈ 319 W
b) P = Fd/t
0.70 (319 W) = (m × 9.8 m/s²) (4.6 m) / (9.6 s)
m = 47.6 kg
Answers:
a) 
b) 
Explanation:
a) The centripetal acceleration 
of an object moving in a uniform circular motion is given by the following equation:
Where:
is the angular velocity of the ball
is the radius of the circular motion, which is equal to the length of the string
Then:
This is the centripetal acceleration of the ball
b) On the other hand, in this circular motion there is a force (centripetal force 
) that is directed towards the center and is equal to the tension (
) in the string:
Where 
is the mass of the ball
Hence:
This is the tension in the string
By definition, the potential energy is:
U = qV
Where,
q: load
V: voltage.
Then, the kinetic energy is:
K = mv ^ 2/2
Where,
m: mass
v: speed.
As the power energy is converted into kinetic energy, we have then:
U = K
Equating equations:
qV = mv ^ 2/2
From here, we clear the speed:
v = root (2qV / m)
Substituting values we have:
v = root ((2 * (1.60218 × 10 ^ -19) * 3600) /9.10939×10^-31))
v = 3.56 × 10 ^ 7 m / s
Then, the centripetal force is:
Fc = Fm
mv ^ 2 / r = qvB
By clearing the magnetic field we have:
B = mv / qr
Substituting values:
B = (9.10939 × 10 ^ -31) * (3.56 × 10 ^ 7) / (1.60218 × 10 ^ -19) * 0.059
B = 3.43 × 10 ^ -3 T
Answer:
A magnetic field that must be experienced by the electron is:
B = 3.43 × 10 ^ -3 T
To solve this problem we will apply the definitions given in Newtonian theory about the Force of gravity, and the Force caused by weight. Both will be defined below, and in equal equilibrium condition to clear the variable concerning acceleration due to gravity. Finally, with the values provided in the statement, it will be replaced.
The equation for the gravitational force between the Earth and the object on the surface of the Earth is
Where,
G = Universal gravitational constant
= Mass of Earth
= Distance between object and center of earth
= Mass of Object
The equation for the gravitational pulling force on the object due to gravitational acceleration is
Equation the two expression we have
This the acceleration due to gravity which is composite constant.
Replacing with our values we have then
The value of composite constant is 
. Here, the composite constant is nothing but the acceleration due to gravity which is constant always.
