A48.5 kg student runs down the sidewalk and jumps with a horizontal speed of 4.25 m/s onto a stationary skateboard. the student and skateboard move down the sidewalk with a speed of 4.05 m/s. a) find the mass of the skateboard. answer in units of kg.

2.39 kg

Explanation:

There is conservation of momentum here in this problem so we will use the following problem:

where the mass of the student is 48.5 kg,

the mass of the skateboard is kg,

the initial speed of the student is 4.25 m/s; and

the speed of the student and skateboard   is 4.05 m/s.

So substituting the given values in the above formula to get:

Therefore, the mass of the skateboard is 2.39 kg.

newton's first law of motion

r = ρ x length / area  

ρ = r x area / length  

ρ is in ohm-meters  

in basic units, it is m³kg/s³a²  

i think this is it.