A 48.0-kg boy, riding a 3.30-kg skateboard at a velocity of 5.10 m/s across a level sidewalk, jumps forward to leap over a wall. Just after leaving contact with the board, the boy's velocity relative to the sidewalk is 6.00 m/s, 7.80° above the horizontal. Ignore any friction between the skateboard and the sidewalk. What is the skateboard's velocity relative to the sidewalk at this instant? Be sure to include the correct algebraic sign with your answer.

−7.2 m/s

Explanation:

We are given that

We have to find the skateboards's velocity relative to the sidewalk at this instant.

Along x- direction

According to law of conservation of momentum

Substitute the values

where is the circuit diagram ?

firearm identification is the process of analyzing the bullets and cartridge cases left at a crime scene to determine if they came from a particular firearm. marks on the bullets and cartridges may be common to every firearm of that type. these are called class characteristics.