A heat engine produces 8200 j of heat while performing 3200 of useful work. what is the efficiency of this engine? (i'm doing something wrong.)

Which ones reflect and emit light? Star, asteroid, sun, Polaris, meteor, earth, moon, comet, mars

In the future, several students living different types of electromagnetic radiation. Which of the following travels through space the fastest? a.

What's period formula

Which best describes what is occurring when a door is almost closed and rays of light fan out from the small opening? absorption interference refraction diffraction

Which data set has the smallest standard deviation? A. 1,6,19,20,85,29,0 B. 22,22,23,23,22,22,23 C. 6, 7, 6, 7, 1004, 980, 350 D. 99, 199, 299, 55, 44,33, 22

A magnet is pushed into the center of a wire loop and then stops. what is the current in the wire loop when the wire stops moving? explain.

Which feature do highland climates have that lower elevation area do not? A tundra where there are no trees A tree line beyond which trees do not grow Permafrost, or a part of the ground that is permanently frozen An ice cap, or a permanent cover of

As shown in the figure below, Cindy rushes 30 mtoward her truck. She notices she forgot her lunch and returns back to the house. Her total travel time is 90s a. What is Cindy's average velocity over the 90s period? b.

Un atleta que recorre 100 m en 12 s

Assuming equal rates of acceleration in both cases, how much farther would you travel if braking from 59 mi/h to rest than from 25 mi/h?