A boy throws a ball up into the air with a speed of 12.3 m/s. The ball has a
mass of 0.25 kg. How much gravitational potential energy will the ball have at
the top of its flight? (Assume there is no air resistance.)

What is the efficiency of an engine that does 80 j of work and exhausts 320 j of heat while taking in 400 j of heat ? a. 10% b. 20% c. 80% d. 25%

The goal of this experiment was to answer the question, "how does diffraction occur? " suppose you formulated this alternate hypothesis: if the gap width is increased while keeping wavelength constant, then the observed diffraction will decrease because the less the ratio between wavelength and gap width is, the smaller the observed diffraction angle will be.to test this hypothesis, you would change the  gap widthdiffraction anglewavelength  and observe the  gap widthdiffraction anglewavelength  in the system.therefore, the independent variable would be the  gap widthdiffraction anglewavelength  and the dependent variable would be the  gap widthdiffraction anglewavelength.

Scientists and engineers design new technologies to solve problems. often, a new technological design will contain a flaw. which of the following is true about such a flaw? a. it should be studied so that the design can be fixed or a new design can be proposed. b. it means that the problem being investigated cannot be solved. c. it means that the people who proposed the design should not be scientists or engineers. d. it makes the technological design useless.