<span>Let L and R be the left and right vertical floor reactions
let T be the tension of the rope
summation of all forces is zero
R + L - 500 - 150- 150 = 0
R + L = 800
since the triangle formed is isosceles triangles, the legs are equal
R = L = 400 N
using the summation of the torque
L [ 4] - T[ 3 - (2 *3/5)] = 0
400 [ 4] - T[ 1.8] = 0
T = 1600/1.8
T = 889 N </span>
Wavenlenth will affect the speed
F = focal lenght = 67.1 cm
u= distance between mirror and object = 16.76 cm
1/f = 1/v + 1/u
1/67.1 = -1/16.76 + 1/u
1/67.1 + 1/16.76 = 1/u
u = 13.41
Question 1's answer is, if we change the length of the string allowed to vibrate, then the frequency (and pitch) of the string vibration will change. This is because the tension of the string determines the pitch.
Question 2's answer is 2. This can be solved by doing simple division. 30/15 = 2.
Question 3's answer is short bars. Each bar on a xylophone produces a different pitch; the shorter the bar, the higher the pitch.
Hope this helps.