A child is on a sled moving down a hill at 27.6 m/s. The combined mass of the sled and child is 60.6 kg. The momentum of the child and sled is .

1672 kgm/s

Explanation:

The momentum of an object can be found by using the formula

momentum = mass × velocity

From the question we have

momentum = 60.6 × 27.6

1672.56 kg.m/s

Hope this helps you

The boat's velocity relative to the riverbank can be resolved into two components. the component going north is 2.7 m/s and the component going west is 1.2 m/s.we add these two vectors and then find the magnitude of the resultant to get the speed.the magnitude of the resultant vector from adding can be obtained by the pythagorean theorem.    to two significant figures, the boat's speed relative to the riverbank is 3.0 m/s.

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