Answer: the waves travel in an horizontal direction while the strings vibrate in a vertical direction.
Answer:The frequency of the echo is slightly decreased
Explanation:
Given
speed of boat 
cliff is 
away
when boat is still , suppose t is the time taken by the echo to reach observer on the boat
But as soon as boat starts moving the distance between cliff and boat decreasing and time for echo to reach observer also decreases
and we know 
therefore frequency of the echo slightly decreased.
Acceleration is the rate at which an object changes its velocity. It defines how much the velocity is changing. The acceleration can be negative and positive. Negative acceleration is when the object slows down, while positive while the object goes faster.
<span>A ball moving at a constant speed around a circular track produces acceleration. </span>
Answer:
As a result, light travels fastest in empty space, and travels slowest in solids. In glass, for example, light travels about 197,000 km/s.
Explanation:
No thats false. If your trying to say is true that people BELIEVED that then yes its true people believed it but if your talking about that question then its false
