A mass 3kg at the temperature 850°c is quickly transferred into a lead calorimeter of negligible heat capacity containing water of mass 500g at 20°c. Evaluate the mass of that boils away given the specific heat capacity as 400JKg-1K-1 and specific heat of vaporization steam as 2.26 × 10^5kg.

What would the difference of spectral lines emitted by hydrogen gas in distant galaxies which is normally found at a wavelength of 21 cm on earth, be observed at 21.1 centimeters?

In the sport of parasailing, a person is attached to a rope being pulled by a boat while hanging from a parachute-like sail. a rider is towed at a constant speed by a rope that is at an angle of 15 ∘ from horizontal. the tension in the rope is 1900 n. the force of the sail on the rider is 30∘ from horizontal. what is the weight of the rider? express your answer with the appropriate units.

The radius of a sphere is increasing at a rate of 9 cm/ sec. find the radius of the sphere when the volume and the radius of the sphere are increasing at the same numerical rate.