Question

A nucleus moving with a velocity →v emits an α-particle. Let the velocities of the α-particle and the remaining nucleus be v1 and v2 and their masses be m1 and m2.
(a) →v,→v1 and →v2 must be parallel to each other.
(b) None of the two of →v,→v1 and →v2 should be parallel to each other.
(c) →v1+→v2 must be parallel to →v
(d) m1→v1+m2→v2 must be parallel to →v

Answer 1

Answer:

A nucleus moving with a velocity →v emits an α-particle. Let the velocities of the α-particle and the remaining nucleus be v1 and v2 and their masses be m1 and m2.

(a) →v,→v1 and →v2 must be parallel to each other.

(b) None of the two of →v,→v1 and →v2 should be parallel to each other.

(c) →v1+→v2 must be parallel to →v

(d) m1→v1+m2→v2 must be parallel to →v

A nucleus moving with a velocity →v emits an α-particle. Let the velocities of the α-particle and the remaining nucleus be v1 and v2 and their masses be m1 and m2.A nucleus moving with a velocity →v emits an α-particle. Let the velocities of the α-particle and the remaining nucleus be v1 and v2 and their masses be m1 and m2.

(a) →v,→v1 and →v2 must be parallel to each other.

(b) None of the two of →v,→v1 and →v2 should be parallel to each other.

(c) →v1+→v2 must be parallel to →v

(d) m1→v1+m2→v2 must be parallel to →v

(a) →v,→v1 and →v2 must be parallel to each other.

(b) None of the two of →v,→v1 and →v2 should be parallel to each other.

(c) →v1+→v2 must be parallel to →v

(d) m1→v1+m2→v2 must be parallel to →v

Answer 2

(d) m1→v1+m2→v2 must be parallel to →v  

Explanation:

• A system conserves linear momentum, which is a vector, if no external force is exercised, the path of nucleus v's velocity is similar to its momentum.
• The momentum after emission of ɑ-particle $m_1 v_1 + m_2 v_2$  will have the same direction as v due to conservation principle.
• By the law of conservation of linear momentum ,Initial momentum is equals to final momentum

Momentum :-  Momentum is defined as the product of a mass and  speed of the particle. Momentum is a quantity of vectors. Hence momentum (vector quantity) has both magnitude and direction .

A nucleus moving with a velocities $v_1$ and $v_2$ emits an ɑ- particle with masses $m_1$ and $m_2$ satisfies the condition  $m_1 v_1 + m_2 v_2$ must be parallel to velocity 'v'