Answer:
2.62seconds
Explanation:
Speed is defined as the ratio of the distance covered by a body with respect to time.
Speed v = Distance (s)/Time (t)
For a traveling sound wave, the distance between the source of a sound and the reflector is '2S'.
Speed v = 2 × distance (S)/Time (T)
V = 2S/t
2S = vt
Given speed of the wave = 342m/s
Distance covered = 450m
t = 2S/v
t = (2×450)/343
t = 900/343
t = 2.62seconds
It will take him 2.62seconds for him to hear his own voice echo off of the wall.
<span>Kinetic energy because it is taking the students to school.</span>
Answer:
<em>The force of kinetic friction between Kiera and the floor is 9.24 N</em>
Explanation:
<u>Friction Force</u>
When an object is moving and encounters friction in rough surfaces, it loses acceleration and/or velocity because the friction force opposes motion.
The friction force when an object is moving on a horizontal surface is calculated by:
Where μ is the coefficient of static or kinetics friction and N is the normal force.
If no forces other then the weight and the normal are acting upon the y-direction, then the weight and the normal are equal in magnitude:
N = W
Thus, the friction force is:
Kiera, the W=330 N girl steps in water that has a coefficient of friction of μ=0.028 with the floor.
The kinetic friction force is:
Fr = 0.028*330
Fr = 9.24 N
The force of kinetic friction between Kiera and the floor is 9.24 N
Answer:
F = - k (x-xo) a graph of the weight or applied force against the elongation obtaining a line already proves Hooke's law.
Explanation:
The student wants to prove hooke's law which has the form
F = - k (x-xo)
To do this we hang the spring in a vertical position and mark the equilibrium position on a tape measure, to simplify the calculations we can make this point zero by placing our reference system in this position.
Now for a series of known masses let's get them one by one and measure the spring elongation, building a table of weight vs elongation,
we must be careful when hanging the weights so as not to create oscillations in the spring
we look for the mass of each weight
W = mg
m = W / g
and we write them in a new column, we make a graph of the weight or applied force against the elongation and it should give a straight line; the slope of this line is sought, which is the spring constant.
The fact of obtaining a line already proves Hooke's law.
