Answer:
The initial velocity was U=22.14m/s
Explanation:
Step one :
Applying the third equation of motion
v² = u²+ 2as
Where v= Final velocity
U =initial velocity
a= acceleration due to gravity
S= distance or displacement
Step two :
V= 0
a= 9.81m/s²
S=25m
U=?
Step three :
Substituting into the equation we have
0²=U²+2*9.81*25
0=U²+490.5
U²=-490.5
U=√490.5
U=22.14m/s
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Answer:
24 cm
Explanation:
Given:
Mass of proton = 1.67 × 10⁻²⁷ Kg
kinetic energy = 2.5 × 10⁻¹³ J
magnetic field in the cyclotron, B = 0.75 T
Now,
Kinetic energy =
= 2.5 × 10⁻¹³ J
where, v is the velocity of the electron
or
= 2.5 × 10⁻¹³ J
or
v² = 2.99 × 10¹⁴
or
v = 1.73 × 10⁷ m/s
also,
centripetal force = magnetic force
or
= qvB
q is the charge of the electron
r is the radius of the dipole magnets
on substituting the respective values, we get
= 1.6 × 10⁻¹⁹ × 0.75
or
r = 0.2408 m ≈ 24 cm
Hence, the correct answer is 24 cm