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 distance travelled by the body on last second of its upwards journey is 4.935m
What is projectile motion?
A projectile is an object or particle that is launched toward the surface of the Earth and moves along a curved path only under the influence of gravity.
To solve this question, consider the horizontal distance to be H and
distance traveled by the body in the last second be d
H=510.2m
Now time taken to reach a height of
510.2 m=
=10.2 seconds
Now,
d=4936m
So, the correct answer is '4.936m'.
To know more about projectile motion visit:
brainly.com/question/11049671
#SPJ4
This question involves the concept of the scalar product.
The magnitude of the scalar product will be "0".
<h3>SCALAR PRODUCT</h3>
The scalar product, also known as the dot product of the two vectors is given by the following formula:
where,
- A.B = Scalar product = ?
- |A| = Mangnitude of vector A = 1 unit
- |B| = Magnitude of Vector B = 1 unit
- θ = Angle between vectors = 90°
Therefore,
A.B = 0
Learn more about scalar product here:
brainly.com/question/6849226
The answer to this is formation of earth and our solar system