The boy’s foot causes the motion. His foot is the one that causes the ball to roll down the hill.
Answer:
On Earth all bodies have a weight, or downward force of gravity, proportional to their mass, which Earth's mass exerts on them. Gravity is measured by the acceleration that it gives to freely falling objects. At Earth's surface the acceleration of gravity is about 9.8 metres (32 feet) per second per second.
Answer:
Final velocity of the car will be -9.28 m/sec
Explanation:
We have given that the car starts from the rest so initial velocity of the car u = 0 m /sec
Acceleration of the car
in negative direction so acceleration will be 
From first equation of motion we know that
v = u+at
So 
So final velocity will be -9.28 m/sec
We did this experiment before, when the rope moves, it represents the waves passing through in from the level of intensity. I hope this is a good answer.
Answer:
A flat, horizontal line
Explanation:
A flat, horizontal line indicates a phase change.
The temperature does not increase because the added heat goes into converting one phase into another.
A is wrong. A downward-sloping line indicates that the temperature is decreasing with time.
C is wrong. An upward-sloping line indicates that the temperature is increasing with time.