At an auto race, a member of the pit crew stands beside the track. a car approaches him at 100 m/s and emits a sound at frequency 1100hz. the air is still and the speed of sound is 340mls. what frequency will the pit crew member hear? a.1560hz b.1420hz c.1640hz d.850hz

As per the formula of Doppler's effect we know that

now we know that

v = 340 m/s

now we will have

so the frequency heard by the crew will be approx 1560 Hz

d is the answer i came up with

answer: the metamorphic rocks are formed when they are exposed to high pressure and high temperatures. this happens when one of the earth's plates comes in contact with the other plate by traveling in opposite directions, straight into each other or slipping under one another. the friction that is caused by this activity results in   melting of rocks and when it cools they are known as metamorphic rocks. this process needs a controlled amount of pressure and temperature otherwise it may turn into magma.