A Carnot engine takes 3000 J from a reservoir at 600 K, does some work, and discards some heat to a reservoir at 300 K. What is its efficiency?

50%

60%

20%

30%

true or false the precision of calculated answers is limited by the least precise measurement used in the calculation

In terms of impulse and conservation of momentum, explain why a glass is much more likely to break if it falls onto a cement floor than if it falls on to a carpeted floor.

An atom gains an additional electron. What is the overall charge of the ion that is formed? elt

How does the kinetic energy of the particles in a hot cup of coffee compare to the kinetic energy of the particles in ice cream? Explain.

If a generator makes 6000 revolutions in two minutes, how many revolutions does it make each second?

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