Answer:
An electric bell is placed inside a transparent glass jar. The bell can be turned on and off using a switch on the outside of the jar. A vacuum is created inside the jar by sucking out the air. Then the bell is rung using the switch. What will we see and hear?
A.
We’ll see the bell move, but we won’t hear it ring.
B.
We won’t see the bell move, but we’ll hear it ring.
C.
We’ll see the bell move and hear it ring.
D.
We won’t see the bell move or hear it ring.
E.
We’ll see the sound waves exit the vacuum pump.
Explanation:
so, the answer to the question is
A.
We'll see the bell move, but we won’t hear it ring.
Answer
given,
time = 10 s
ship's speed = 5 Km/h
F = m a
a is the acceleration and m is mass.
In the first case
F₁=m x a₁
where a₁ = difference in velocity / time
F₁ is constant acceleration is also a constant.
Δv₁ = 5 x 0.278
Δv₁ = 1.39 m/s
![a_1=\dfrac{1.39}{10}](https://tex.z-dn.net/?f=a_1%3D%5Cdfrac%7B1.39%7D%7B10%7D)
a₁ = 0.139 m/s²
F₂ =m x a₂
F₃ = F₂ + F₁
Δv₃ = 19 x 0.278
Δv₃ = 5.282 m/s
a₃=Δv₂ / t
![a_3=\dfrac{5.282}{10}](https://tex.z-dn.net/?f=a_3%3D%5Cdfrac%7B5.282%7D%7B10%7D)
a₃ = 0.5282 m²/s
m a₃=m a₁ + m a₂
a₃ = a₂ + a₁
0.5282 = a₂ + 0.139
a₂=0.3892 m²/s
F₂ = m x 0.3892...........(1)
F₁ = m x 0.139...............(2)
F₂/F₁
ratio = ![\dfrac{0.3892}{0.139}](https://tex.z-dn.net/?f=%5Cdfrac%7B0.3892%7D%7B0.139%7D)
ratio = 2.8
Answer:
Part a)
%
Part b)
%
Explanation:
As we know that total power used in the room is given as
![P = P_1 + P_2 + P_3 + P_4](https://tex.z-dn.net/?f=P%20%3D%20P_1%20%2B%20P_2%20%2B%20P_3%20%2B%20P_4)
here we have
![P_1 = (110)(3) = 330 W](https://tex.z-dn.net/?f=P_1%20%3D%20%28110%29%283%29%20%3D%20330%20W)
![P_2 = 100 W](https://tex.z-dn.net/?f=P_2%20%3D%20100%20W)
![P_3 = 60 W](https://tex.z-dn.net/?f=P_3%20%3D%2060%20W)
![P_4 = 3 W](https://tex.z-dn.net/?f=P_4%20%3D%203%20W)
![P = 330 + 100 + 60 + 3](https://tex.z-dn.net/?f=P%20%3D%20330%20%2B%20100%20%2B%2060%20%2B%203)
![P = 493 W](https://tex.z-dn.net/?f=P%20%3D%20493%20W)
Part a)
Since power supply is at 110 Volt so the current obtained from this supply is given as
![110\times i = 493](https://tex.z-dn.net/?f=110%5Ctimes%20i%20%3D%20493%20)
![i = 4.48 A](https://tex.z-dn.net/?f=i%20%3D%204.48%20A)
now resistance of transmission line
![R = \frac{\rho L}{A}](https://tex.z-dn.net/?f=R%20%3D%20%5Cfrac%7B%5Crho%20L%7D%7BA%7D)
![R = \frac{(2.8 \times 10^{-8})(10\times 10^3)}{\pi(4.126\times 10^{-3})^2}](https://tex.z-dn.net/?f=R%20%3D%20%5Cfrac%7B%282.8%20%5Ctimes%2010%5E%7B-8%7D%29%2810%5Ctimes%2010%5E3%29%7D%7B%5Cpi%284.126%5Ctimes%2010%5E%7B-3%7D%29%5E2%7D)
![R = 5.23 \ohm](https://tex.z-dn.net/?f=R%20%3D%205.23%20%5Cohm)
now power loss in line is given as
![P = i^2 R](https://tex.z-dn.net/?f=P%20%3D%20i%5E2%20R)
![P = (4.48)^2(5.23)](https://tex.z-dn.net/?f=P%20%3D%20%284.48%29%5E2%285.23%29)
![P = 105 W](https://tex.z-dn.net/?f=P%20%3D%20105%20W)
Now percentage loss is given as
![percentage = \frac{loss}{supply} \times 100](https://tex.z-dn.net/?f=percentage%20%3D%20%5Cfrac%7Bloss%7D%7Bsupply%7D%20%5Ctimes%20100)
![percentage = \frac{105}{493} \times 100](https://tex.z-dn.net/?f=percentage%20%3D%20%5Cfrac%7B105%7D%7B493%7D%20%5Ctimes%20100)
%
Part b)
now same power must have been supplied from the supply station at 110 kV, so we have
![110 \times 10^3 (i ) = 493](https://tex.z-dn.net/?f=110%20%5Ctimes%2010%5E3%20%28i%20%29%20%3D%20493)
![i = 4.48\times 10^{-3} A](https://tex.z-dn.net/?f=i%20%3D%204.48%5Ctimes%2010%5E%7B-3%7D%20A)
now power loss in line is given as
![P = i^2 R](https://tex.z-dn.net/?f=P%20%3D%20i%5E2%20R)
![P = (4.48 \times 10^{-3})^2(5.23)](https://tex.z-dn.net/?f=P%20%3D%20%284.48%20%5Ctimes%2010%5E%7B-3%7D%29%5E2%285.23%29)
![P = 1.05 \times 10^{-4} W](https://tex.z-dn.net/?f=P%20%3D%201.05%20%5Ctimes%2010%5E%7B-4%7D%20W)
Now percentage loss is given as
![percentage = \frac{loss}{supply} \times 100](https://tex.z-dn.net/?f=percentage%20%3D%20%5Cfrac%7Bloss%7D%7Bsupply%7D%20%5Ctimes%20100)
![percentage = \frac{1.05 \times 10^{-4}}{493} \times 100](https://tex.z-dn.net/?f=percentage%20%3D%20%5Cfrac%7B1.05%20%5Ctimes%2010%5E%7B-4%7D%7D%7B493%7D%20%5Ctimes%20100)
%
Answer:
The coefficient of friction and acceleration are 0.37 and 2.2 m/s²
Explanation:
Suppose we find the coefficient of friction and the acceleration of the 100 kg block during the time that the 60 kg block remains in contact.
Given that,
Mass of block = 60 kg
Acceleration = 2.0 m/s²
Mass = 100 kg
Horizontal force = 340 N
Let the frictional force be f.
We need to calculate the frictional force
Using balance equation
![F-f=ma](https://tex.z-dn.net/?f=F-f%3Dma)
Put the value into the formula
![340-f=60\times2.0](https://tex.z-dn.net/?f=340-f%3D60%5Ctimes2.0)
![f=340-60\times2.0](https://tex.z-dn.net/?f=f%3D340-60%5Ctimes2.0)
![f=220\ N](https://tex.z-dn.net/?f=f%3D220%5C%20N)
We need to calculate the coefficient of friction
Using formula of friction force
![f= \mu mg](https://tex.z-dn.net/?f=f%3D%20%5Cmu%20mg)
![\mu=\dfrac{f}{mg}](https://tex.z-dn.net/?f=%5Cmu%3D%5Cdfrac%7Bf%7D%7Bmg%7D)
![\mu=\dfrac{220}{60\times9.8}](https://tex.z-dn.net/?f=%5Cmu%3D%5Cdfrac%7B220%7D%7B60%5Ctimes9.8%7D)
![\mu =0.37](https://tex.z-dn.net/?f=%5Cmu%20%3D0.37)
We need to calculate the acceleration of the 100 kg block
Using formula of newton's law
![F = ma](https://tex.z-dn.net/?f=F%20%3D%20ma)
![a=\dfrac{F}{m}](https://tex.z-dn.net/?f=a%3D%5Cdfrac%7BF%7D%7Bm%7D)
![a=\dfrac{220}{100}](https://tex.z-dn.net/?f=a%3D%5Cdfrac%7B220%7D%7B100%7D)
![a=2.2\ m/s^2](https://tex.z-dn.net/?f=a%3D2.2%5C%20m%2Fs%5E2)
Hence, The coefficient of friction and acceleration are 0.37 and 2.2 m/s²
Answer:
1500 divided by 150(15m x 10m/s^2) = 10