Let k_{1} be the initial kinetic energy,k_{2} be the final kinetic energy.

let p_{1} be intial momentum & p_{2} be final momentum.

From question we have,

k_{2}=k_{1}+100%k_{1}

k_{2}=k_{1}+k_{1}=2k_{1}

1\2(mV_{2})^{2}=2(1\2mV_{1}^{2})

V_{2}=√2V_{1}

on mutiplying by mass m,

mV_{2}=√2mV_{1}

p_{2}=√2p_{1}. now,

Δp=p_{2}-p_{1}

=>p_{1}(√2-1)

%age of change in momentum=100(Δp\p_{1})

= 100(√2 - 1) %

=(1.414-1)100

=41.4%