Question

1. a sea bird builds its nest on a ledge above the ocean, where it fishes for food. when does the bird have the most potential energy? a. flying at 10 m/s 10 m above the ocean b. sitting in its nest 20 m above the ocean c. swimming on the ocean surface at 2 m/s d. diving for fish 3 m below the ocean surface

Explanation:

Potential energy (PE) is given by the formula \( PE = mgh \), where \( m \) is mass, \( g \) is acceleration due to gravity, and \( h \) is height above a reference point (here, the ocean surface). Mass and \( g \) are constant for the bird, so PE depends on height. Higher height means more PE.

• Option A: Height = 10 m (flying, has kinetic energy too, but PE depends on height).
• Option B: Height = 20 m (sitting, height is highest among options).
• Option C: Height = 0 m (ocean surface, PE is lowest here).
• Option D: Height = -3 m (below surface, PE is less than at positive heights).

So the bird has the most potential energy when sitting in its nest 20 m above the ocean (highest height).

Answer:

B. sitting in its nest 20 m above the ocean