The answer is <span>C. 49 m/s
The kinetic equation is:
v2 = v1 + a * t
v1 - initial velocity
v2 - final velocity
a - gravitational acceleration
t - time
We know:
v2 = ?
v1 = 0 (in free fall
a = 9.8 m/s
t = 5
</span>v2 = v1 + a * t
v2 = 0 + 9.8 * 5
v2 = 0 + 49
v2 = 49 m/s
KE = 1/2 mv^2 is the relationship betwee mass and kinetic energy
According to the net force, the acceleration of the book is 16.47 m/s².
We need to know about force to solve this problem. According to second Newton's Law, the force applied to an object will be proportional to mass and acceleration. Hence, it can be written as
∑F = m . a
where F is force, m is mass and a is acceleration
From the question above, we know that
m = 3 kg
g = 9.8 m/s²
F1 = 20 N
Find the net force
∑F = F1 + W
∑F = 20 + m . g
∑F = 20 + 3 . 9.8
∑F = 20 + 29.4
∑F = 49.4 N
Find the acceleration
∑F = m . a
49.4 = 3 . a
a = 16.47 m/s²
Find more on force at: brainly.com/question/25239010
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