Acopper weight weighs 268 n in air and displaces an amount of water weighing 30. n . what is the weight of the copper measured in water?

238 N

Explanation:

Archimedes principle states that every body submerged in a fluid is buoyed up by a force equal to the weight of the fluid displaced by the body:

Here, is the immersed weight of the copper, and is the weight of the displaced water. Due to this, the copper has a weight when immersed in water of:

if you already have the answer to (a), then just work out how many periods there are in 1 minute, and that's the answer to (c).

5 w for 1hr = 5x60x60 joules=300x60=3000x6=18,000j as total energy conversion. efficiency of bulb needed for radiant to thermal within 18000