Answer:
<em>a = 7.6\ mph/s</em>
Explanation:
<u>Motion With Constant Acceleration </u>
It's a type of motion in which the velocity of an object changes uniformly in time.
The equation that describes the change of velocities is:
Where:
a = acceleration
vo = initial speed
vf = final speed
t = time
Solving the equation [for a:
The car accelerates from vo=0 to vf=60 mph in t=7.9 s, thus the acceleration is:
a = 7.6\ mph/s
Answer:
A. potential energy is 258720 Joule
Explanation:
A.Gravitational potential energy is: PE = m × g × h
velocity = 15.33 m/s when the car reaches the bottom of the hill.
where, m = mass
g = acceleration due to gravity
h = height from the bottom of hill.
The potential energy is : m×g×h
=(2200×9.8×12)
=258720 Joule
B. at the bottom of the hill, the potential energy is converted into kinetic energy so PE at top = KE at bottom
kinetic energy= (
)
where v = velocity
m= mass
therefore, v=
or, v=
or, v=15.33 m/s