Answer:
a. 1.5 m/s
Explanation:
We will apply the law of conservation of energy in this situation between the initial position and the lowest point of the swing:
[tex]m_{1}u_{1} + m_{2}u_{2} = m_{1}v_{1} + m_{2}v_{2}\\[/tex]
where,
m₁ = mass of ball = 1.6 kg
m₂= mass of block = 0.8 kg
u₁ = initial speed of ball = 0 m/s
u₂ = initial speed of block = 0 m/s
v₁ = final speed of ball = ?
v₂ = final speed of block = 3 m/s
Therefore,
[tex](1.6\ kg)(0\ m/s)+(0.8\ kg)(0\ m/s)=(1.6\ kg)(v_{1})+(0.8\ kg)(3\ m/s)\\\\v_{1} = \frac{2.4\ N.s}{1.6\ kg}\\[/tex]
v₁ = 1.5 m/s
Therefore, the correct option is:
a. 1.5 m/s