A freshly brewed cup of coffee has temperature 95°c in a 20°c room. when its temperature is 65°c, it is cooling at a rate of 1°c per minute. when does this occur? (round your answer to two decimal places.)

High pitch sounds are characterized by song waves that have a

A model rocket is fired vertically upward from rest. Its acceleration for the first three seconds is a (t) = 66 t, at which time the fuel is exhausted and it becomes a freely "falling" body.

The storage method used for radioactive wastes generated from fission nuclear reactors must be designed to last for how long? A. months B. years C. centuries D. weeks

A bird-watcher is hoping to add the white-throated sparrow to her "life list" of species. How far could she be from the bird described in example 14-8 and still be able to hear it? Assume no reflections or absorption of the sparrow's sound.

Why do atoms form bonds? A. to decrease the number of electron shells in an atom B. to increase the number of electrons orbiting the nucleus C. to transfer electron shells between atoms D. to create a completely full outer shell of electrons

Consider a helium balloon on a string tied to the seat of your stationary car. The windows are closed, so there is no air motion within the car. The car begins to accelerate forward. Which way will the balloon lean, forward or backward

The force of gravity acts upon meteors from the rocky asteroid belt between mars and Jupiter. Where is the force of gravity most likely to pull these meteors

Sally turns on her cellular telephone to speak to her friend who is located thousands of miles away. Which of the following best describes how such a telephone is able to transmit and receive information? A.

Calculate the gravitational potential energy relative to the ground when an 82 kg person climbs to the top of a 2.0 m stepladder.

A rock is thrown from a cliff and hits the ground five seconds later at a distance of 50 m from the cliff how high was a cliff