Q. 14.4( 10 Votes )
An alpha particle is projected vertically upward with a speed of 3.0 × 104 kg s–1 in a region where a magnetic field of magnitude 1.0 T exists in the direction south to north. Find the magnetic force that acts on the α-particle.
Answer :
Given -
Speed of the alpha particle in upward direction,
v = 3 × 104 km/s
since 1Km = 1000m
⇒ v = 3 × 107 m/s
Magnetic field, B = 1.0 T
Charge on the alpha particle is given as ,
where e is the charge of an electron.
⇒ q = 2 × 1.6 × 10−19 C,
We need to calculate the magnetic force that acts on the α-particl
The direction of magnetic force can be found using Fleming’s left-hand rule.
The direction of the magnetic field is from south to north.
We know, Lorentz force F is given by -
where,
q = charge
v = velocity of the charge
B=magnetic field
and
θ= angle between V and B
Now, magnetic force acting on the α -particle,
Substituting the values
= 2 × 1.6 × 10−19 × 3 × 107 × 1
= 9.6 × 10−12 N
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