Answer:
The kinetic energy of the cell phone is 9J
Explanation:
The kinetic energy is the energy possessed by a body by virtue of motion.
The kinetic energy is expressed as
KE= 1/2m(v)²
Given data
Mass of cell phone m= 80g--to kg=80/1000= 0.08kg
Velocity of cell phone v= 15m/s
Substituting our given data we have
KE= 1/2*0.08(15)²
KE= (0.08*225)/2
KE=18/2
KE= 9J
consider the motion along the horizontal direction :
v₀ = initial velocity in horizontal direction as the ball rolls off the table = 3.0 m/s
X = horizontal displacement of the ball = 2.0 m
a = acceleration along the horizontal direction = 0 m/s²
t = time taken to land = ?
using the kinematics equation
X = v₀ t + (0.5) a t²
2.0 = 3.0 t + (0.5) (0) t²
t = 2/3
consider the motion of the ball along the vertical direction
v₀ = initial velocity in vertical direction as the ball rolls off the table = 0 m/s
Y = vertical displacement of the ball = height of the table = h
a = acceleration along the vertical direction = 9.8 m/s²
t = time taken to land = 2/3
using the kinematics equation
Y = v₀ t + (0.5) a t²
h = 0 t + (0.5) (9.8) (2/3)²
h = 2.2 m
C 2.2 m
B is the correct answer hope that helped
But what are the choices??
