Question

A 91.5 kg football player running east at 3.73 m/s tackles a 63.5 kg player running east at 3.09 m/s. what is their velocity afterward? PLEASE HELP

Answer 1

Their velocity afterward is v=3.467 m/s

Step-by-step explanation:

Given:

Mass of the first football player= 91.5 kg

Initial velocity of the football player 3.73 m/s

Mass of second football player=63.56 kg

Initial velocity of the second football player=3.09 m/s

To find:

Final velocity of both players=?

Solution:

According to the law of conservation of momentum,

Initial momentum =final momentum

mathematically represented as

`m_1u_1+m_2u_2=m_1v_1+m_2v_2`...........................(1)

where

`u_1`=intial velocity of the football player

`u_2` = inital velocity of second football player

`v_1`=finall velocity of the first football player

`v_2`=final velocity of second football player

after tackling , both the football players moves with the same velocity,

so
`v_1=v_2=v`

Hence equation (1) becomes

`m_1u_1+m_2u_2=(m_1+m_2)v`

`v=(m_1u_1+m_2u_2)/((m_1+m_2))`

now substituting the values,

`v=((91.5*+3.73)+(63.5*3.09))/((91.5+63.5))`
`v=((341.29+196.210))/(155)`

`v=(537.5)/(155)`

v=3.467 m/s