Answer:
13.23J
Explanation:
PE = m*g*h
PE = (3 kg ) * (9.8 m/s/s) * (0.45 m)
You just identified the image as a "reflection", so it's a pretty good bet that
the phenomenon involves reflection somehow.
Your dog can see his reflection in a mirror inside the house just as easily
as in the surface of the pond. My dogs do it all the time. The phenomenon
doesn't require water.
It's reflection of light waves.
Answer:
The car is decelerating and its acceleration is negative.
Explanation:
First thing to consider. The car traveling direction is not important to answer the question.
Second, there are two affirmations on each sentence. So, lets take definitions:
Deceleration: Reducing the acceleration, from one value to another. No matter if the acceleration for the moment is positive or negative.
Acceleration negative: the driver is applying a force to make speed=0, the sign of this force must negative in order for the car to stop, other way it will go faster. Acceleration is the change rate of speed, if the speed is going down, the total acceleration until cars stops must be negative.