A bird,accelerating from rest at a constant rate,experiences a displacement of 25 m in 15 s.What is the final velocity after 15 s?
A)2.5 m/s
B)1.7 m/s
C)3.3 m/s
D)3.8 m/s
E)zero

Question

A bird,accelerating from rest at a constant rate,experiences a displacement of 25 m in 15 s.What is the final velocity after 15 s?​
A)2.5 m/s
B)1.7 m/s
C)3.3 m/s
D)3.8 m/s
E)​zero

Quizplus · Accepted Answer

We can use the formula:

v = u + at

where:
v = final velocity (what we need to find)
u = initial velocity (which is 0 since it starts from rest)
a = acceleration (constant rate)
t = time taken (15 seconds)

We also know the displacement, which can be used to find acceleration:

s = ut + 1/2 at^2

25 = 0(15) + 1/2 a (15)^2

a = 25/112.5 = 0.2222 m/s^2

Now we can substitute these values into the first equation:

v = 0 + (0.2222)(15)

v = 3.33 m/s

Therefore, the final velocity after 15 seconds is approximately 3.3 m/s, which is represented by choice letter C.

A Bird,accelerating from Rest at a Constant Rate,experiences a Displacement