The boy’s foot causes the motion. His foot is the one that causes the ball to roll down the hill.
Answer:
The forces are a convergent
Explanation:
Answer:
Option (c) is correct.
Explanation:
The apparent change in the frequency of light due to the relative motion between the source and the observer is called Doppler's effect.
When the source is moving towards the observer which is at rest, the apparent frequency increases and if the observer is moving away the frequency of sound decreases.
It occurs for both light and sound.
So, to explain the blue shift of light in the universe is due to the Doppler's effect of light.
Answer:
135° (degrees)
Explanation:
The Earth rotates 360° in about 24 h
How many degrees in 1 hour
So, in 1 hour the Earth rotates 15 degrees. This means that a person would have to reset their watch by 1 hour after travelling 15 degrees
In 9 hours
So, a person would have to travel 135 degrees in order to reset their watch by 9 hours.
