Given data
*The particle A has kinetic energy is U_a = 300 J
*Particle B has a mass is m_b = 2 × m_a
*Particle B has a speed is v_b = 1/2 × v_a
The formula for the kinetic energy of the particle B is given as
[tex]U_b=\frac{1}{2}m_bv^2_b[/tex]Substitute the known values in the above expression as
[tex]\begin{gathered} U_b=\frac{1}{2}(2\times m_a)(\frac{1}{2}\times v_a)^2 \\ =\frac{1}{4}m_av^2_a \\ =\frac{1}{2}\times\frac{1}{2}m_av^2_a \\ =\frac{1}{2}\times300 \\ =150\text{ J} \end{gathered}[/tex]Hence, the kinetic energy of the particle B is U_b = 150 J
