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A rifle shoots a projectile of mass 1kg into a block. The speed of the projectile before it hits is 100m/s. The projectile sticks in the block and they move together at 2 m/s. What is the mass of the block, in kg

User PasteBT
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1 Answer

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To solve this problem it is necessary to apply the conservation equations of the momentum, for which it allows us to find the mass of object two, which was the product of an inelastic shock. Mathematically the momentum can be described as


m_1v_1+m_2v_2 = (m_1+m_2)V_f

Where,


m_(1,2) = Mass of each object


v_(1,)2 = Velocity of each object


V_f= Final Velocity

Our values are given as,


m_1 = 1 kg


v_1 = 100 m/s


v_2 = 0 \rightarrow The block remains at rest


V_f = 2 m/s

Substituting,


m_1v_1+m_2v_2 = (m_1+m_2)V_f


1*100 + 0 = (1 + m_2)*2


100 = 2 + 2m_2


98 = 2m_2


m_2 = 49 kg

Therefore the mass of the block is 49Kg.

User Brett Lempereur
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