Answer:
.04 kg m/s
Step-by-step explanation:
Momentum is simply mass multiplied by velocity given by p = mv. You can consider momentum as mass in motion.
Before the collision, the data given for the toy train:
v = 0.5m/s
m = 75g
We need to convert grams into the SI unit of mass, kg.
75g / 1000g * 1kg = 0.075kg
Using p = mv, we can determine:
p = 0.075kg * 0.5m/s = 0.0375 kg m/s
Rounding to the value of 1 sig-fig, it comes out to be 0.04 kg m/s.