Answer: -7J
Explanation:
To determine the change in potential energy, use the equation ΔPE=mgΔh
Δ
PE=mg
Δ
h
, where m is the mass, g= 9.8 m/s2
g= 9.8 m/s
2
, and Δh is the change in height. Hence, we have that the potential energy PE=4.0 kg×9.8 m/s2×-2.0 m=-78 J
PE=4.0 kg
×
9.8 m/s
2
×
-2.0 m=-78 J
. To verify that this is correct, note that since the cat changes the potential energy to kinetic energy by jumping, the potential energy decreases. Hence, the potential energy should be negative.
The answer is c because the big bang theory is about how the universe was created by infinite energy
Answer:

Explanation:
Mass of Earth, 
Mass of Moon, 
The distance between Earth and the Moon is, 
We need to find the force of gravitational attraction between the Earth and the moon. The force of gravity is given by :

So, the required force is
.
The impulse experienced is -18,000 kg m/s
Explanation:
The impulse exerted on an object is equal to the change in momentum of the object. Mathematically:

where
m is the mass of the object
v is the final velocity of the object
u is the initial velocity
is the change in momentum
I is the impulse
In the collision in this problem,
m = 1300 kg is the mass of the car
u = 11 m/s is the initial velocity
v = -2.5 m/s is the final velocity (negative, since it is in the opposite direction)
Substituting, we find

So the closest choice is
-18,000 kg m/s
Learn more about impulse and change in momentum:
brainly.com/question/9484203
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Answer:
<h2>10,000 J</h2>
Explanation:
The kinetic energy of an object can be found by using the formula

m is the mass
v is the velocity
From the question we have

We have the final answer as
<h3>10,000 J</h3>
Hope this helps you