Akettle heats 1.75 kg of water. the specific latent heat of vaporisation of water is 3.34 x 106 j/kg. how much energy would be needed to boil off the water? write the answer out in full (i. e. not in standard form).

Suppose a wheel with a tire mounted on it is rotating at the constant rate of 2.15 times a second. a tack is stuck in the tire at a distance of 0.373 m from the rotation axis. noting that for every rotation the tack travels one circumference (a) find the tack's tangential speed. (b) what is the tacks radial acceleration?

The two stars in a certain binary star system move in circular orbits. the first star, alpha, has an orbital speed of 36 km/s. the second star, beta, has an orbital speed of 12 km/s. the orbital period is 137 d. a) what is the mass of the star alpha? b) what is the mass of the star beta?

This is the number of complete movements of a wave per second.