Answer:
a) the cheetah's top speed is 64.4 miles/hr
b) time taken to reach top speed is 3.3 seconds
Explanation:
Given the data in the question;
Cheetahs can accelerate to a speed of 21.8 m/s in 2.50 s.
They can continue to accelerate to reach a top speed of 28.8 m/s.
a) Express the cheetah's top speed in mi/h. (Express your answer to three significant figures.)
The cheetah's top speed = 28.8 m/s = ( 28.8 × 2.237 ) miles/hr
= 64.4256 ≈ 64.4 miles/hr
Therefore, the cheetah's top speed is 64.4 miles/hr
b) Starting from a crouched position, how long does it take a cheetah to reach its top speed.
given that
v₁ = 21.8 m/s and t₁ = 2.50 s
let a represent the acceleration of the cheetah
From the First Equation of Motion;:
v = u + at
we substitute
21.8 = 0 + ( a × 2.50 )
21.8 = a × 2.50
a = 21.8 / 2.50
a = 8.72 m/s²
Now, let the time taken by cheetah to reach top speed ( 28.8 m/s ) be t
so from the first equation of motion;
v = u + at
we substitute
28.8 = 0 + ( 8.72 × t )
t = 28.8 / 8.72
t = 3.3 seconds
Therefore, time taken to reach top speed is 3.3 seconds
