Energy comes from what

Jacques and Georgette meet in the middle of a lake while paddling in their canoes. They come to a complete stop and talk for a while. When they are ready to leave, Jacques pushes Georgette's canoe with a force F to separate the two canoes.

On a part-time job, you are asked to bring a cylindrical iron rod of density 7800 kg/m3, length 78.4 cm and diameter 2.30 cm from a storage room to a machinist. Calculate the weight of the rod, w. Assume the free-fall acceleration is g

How does sound wave travel through a medium

How long does it take electrons to get from a car battery to the starting motor? Assume the current is 280 A and the electrons travel through a copper wire with cross-sectional area 0.44 cm2 and length 0.85 m.

A rock weighing 20 n (mass = 2 kg) is swung in a horizontal circle of radius 2 m at a constant speed of 6 m/s. what is the centripetal acceleration of the rock?

Consider a Young's two-slit experiment in which the wavelength of light is 37% smaller than the distance between the slits.

Which of the following situations would produce an average velocity of zero? A) a round-trip to school and back B) a horse galloping in a field C) the criss-crossing path of a flying bug D) a trip, first to the moon, then onto Mars

A 111.6 g sample of iron was heated from 0°C to 20°C. It absorbed 1004 J of energy. What is the specific heat capacity of iron?

A car is driving towards a brick wall at a constant velocity (don't try this at home!) and the driver honks the horn of the car. the sound of the horn reflects from the wall and the echo is heard by the driver.

Mass number of an atom with 11 protons