Answer:
Explanation:
You are looking for the resistance to start with
W = E * E/R
75 = 240 * 240 / R
75 * R = 240 * 240
R = 240 * 240 / 75
R = 57600 / 75
R = 768
Now let's see what happens when you try putting this into 110
W = E^2 / R
W = 120^2 / 768
W = 18.75
So the wattage is rated at 75. 18.75 is a far cry from that. I think they intend you to set up a ratio of
18.75 / 75 = 0.25
This is the long sure way of solving it. The quick way is to realize that the voltage is the only thing that is going to change. 120 * 120 / (240 * 240) = 1/2*1/2 = 1/4 = 0.25
Valleys, waterfalls, flood plains, meanders, and oxbow lakes
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
