The doppler shift was first tested in 1845
by the french scientist b. ballot. he had
a trumpet player sound a 414 hz note while
riding on a flat-car pulled by a locomotive. at
the same time, a stationary trumpeter played
the same note. ballot heard 4 beats/s.
how fast was the train moving toward him?
the speed of sound in air is 343 m/s .
answer in units of m/s

Acave rescue team lifts an injured spelunker directly upward and out of a sinkhole by means of a motor-driven cable. the lift is performed in three stages, each requiring a vertical distance of 11.0 m: (a) the initially stationary spelunker is accelerated to a speed of 4.80 m/s; (b) he is then lifted at the constant speed of 4.80 m/s; (c) finally he is decelerated to zero speed. how much work is done on the 78.0 kg rescue by the force lifting him during each stage

Answer asap 50 points which of the following illustrates how a venus fly trap senses that an insect has landed in its open leaves? 1. using tiny hairs, the leaves sense a change in light. 2. using tiny hairs, the leaves taste a chemical. 3. using tiny hairs, the leaves detect a touch. 4. using tiny hairs, the leaves sense a change in water levels.

Adiagram show how a converging lens can produce a real image and virtual image