Answer:
<h2>441 J</h2>
Explanation:
The potential energy of a body can be found by using the formula
PE = mgh
where
m is the mass
h is the height
g is the acceleration due to gravity which is 9.8 m/s²
From the question we have
PE = 30 × 9.8 × 1.5
We have the final answer as
<h3>441 J</h3>
Hope this helps you
The direction of its displacement wil be
c.northeast
In fact, the dog walks north for 10 meters and east for another 10 meters. The path of the dog can be represented with two vectors, A pointing north (of magnitude 10 meters) and B pointing east (of magnitude 10 meters). The direction of the resultant vector (due to east) will be given by


and the direction will be north-east.
The formula for potential energy is
E(p) = mgh
(Mass x gravity x height)
Therefore energy = (5.3)(9.8)(6.6)
= 342.8 J
How did I get 9.8?
9.8 is the constant for gravity
The kinetic energy of an object of mass m and velocity v is given by

Let's call

the initial speed of the car, so that its initial kinetic energy is

where m is the mass of the car.
The problem says that the car speeds up until its velocity is twice the original one, so

and by using the new velocity we can calculate the final kinetic energy of the car

so, if the velocity of the car is doubled, the new kinetic energy is 4 times the initial kinetic energy.
Answer:
Jesseca wanted to create a material that reflected most of the light that fell on it.
Explanation: The Graphite was the material in the passage that had reflected most of the light.