Answer:
The speed of the chair just before impact is 22.54 m/s
Explanation:
From the question,
The chair was initially at rest, that is, the initial velocity of the chair is 0 m/s.
Since the chair was thrown from a balcony, the chair will fall freely due to gravity.
To determine the speed of the chair just before impact, we will determine the final velocity of the chair.
From one of the equations of linear motion for objects falling freely due to gravity,
v = u + gt
Where v is the final velocity
u is the initial velocity
g is the acceleration due to gravity (Take g = 9.8 m/s²)
and t is time
From the question,
u = 0 m/s
t = 2.3 secs
Then, v = u + gt becomes
v = 0 + (9.8)(2.3)
v = 9.8 × 2.3
v = 22.54 m/s
Hence, the speed of the chair just before impact is 22.54 m/s.
Answer:
116.7 Hz
Explanation:
Let there are two wires A and B.
Tension in wire A = T
Tension in wire B = 2T
Length of wire A = L
Length of wire B = 2L
fundamental frequency in wire A, fA = 330 Hz
let the fundamental frequency in wire B is fB.
The formula for the fundamental frequency is given by
![f=\frac{1}{2L}\sqrt{\frac{T}{\mu }}](https://tex.z-dn.net/?f=f%3D%5Cfrac%7B1%7D%7B2L%7D%5Csqrt%7B%5Cfrac%7BT%7D%7B%5Cmu%20%7D%7D)
where, μ is the mass per unit length
mass per unit length of wire A = Area of wire A x density
mass per unit length of wire B = Area of wire B x density
![\frac{\mu _{A}}{\mu _{B}}=\frac{d_{A}^{2}}{4d_{A}^{2}}=\frac{1}{4}](https://tex.z-dn.net/?f=%5Cfrac%7B%5Cmu%20_%7BA%7D%7D%7B%5Cmu%20_%7BB%7D%7D%3D%5Cfrac%7Bd_%7BA%7D%5E%7B2%7D%7D%7B4d_%7BA%7D%5E%7B2%7D%7D%3D%5Cfrac%7B1%7D%7B4%7D)
So,
![\frac{f_{A}}{f_{B}}=\frac{L_{B}}{L_{A}}{\sqrt{\frac{T_{A}\mu _{B}}{T_{B}\mu _{A}}}}](https://tex.z-dn.net/?f=%5Cfrac%7Bf_%7BA%7D%7D%7Bf_%7BB%7D%7D%3D%5Cfrac%7BL_%7BB%7D%7D%7BL_%7BA%7D%7D%7B%5Csqrt%7B%5Cfrac%7BT_%7BA%7D%5Cmu%20_%7BB%7D%7D%7BT_%7BB%7D%5Cmu%20_%7BA%7D%7D%7D%7D)
![f_{B}=\frac{f_{A}}{2\sqrt{2}}](https://tex.z-dn.net/?f=f_%7BB%7D%3D%5Cfrac%7Bf_%7BA%7D%7D%7B2%5Csqrt%7B2%7D%7D)
fB = 330 / 2.828
fB = 116.7 Hz
Thus, the frequency in the second wire is 116.7 Hz.
Primary Circular Reactions (1-4 months): This substage involves coordinating sensation and new schemas. For example, a child may suck his or her thumb by accident and then later intentionally repeat the action. These actions are repeated because the infant finds them pleasurable.