Answer:
Explanation:
Two frequencies with magnitude 150 Hz and 750 Hz are given
For Pipe open at both sides
fundamental frequency is 150 Hz as it is smaller
frequency of pipe is given by

where L=length of Pipe
v=velocity of sound
for n=1
and f=750 is for n=5
thus there are three resonance frequencies for n=2,3 and 4
For Pipe closed at one end
frequency is given by

for n=0


for n=2

Thus there is one additional resonance corresponding to n=1 , between
and 
Answer:
It will take 4 sec rock to comes its original point
Explanation:
It is given that the rock comes to its original point
So displacement S = 0 m
Initial velocity u = 19.6 m/sec
Acceleration due to gravity 
According to second equation of motion 


t = 4 sec
Answer:
Smaller refractive power
Explanation:
The refractive power of an eye is the extent to which it can converge or diverge the light rays.
Near point is the the closest point for an eye such that when an object is placed at that point the image it forms is sharp and clearly visible to the eye.
A the person ages, the ciliary muscles of the eyes weakens and as a result the lens contracts and the formation of the image takes place behind the retina instead of forming at the retina.
Thus the near point also increases and the refractive power becomes smaller.
Answer:
e) electrons are transferred from the rod to the silk.
Explanation:
An initially neutral glass rod contains equal number of electron and proton.
If the rod becomes positively charged after being rubbed with silk, then the rod must have lost some its electron to the silk since electrons are more mobile than protons, leaving the rod with excess positive charge (protons), and the silk will be negatively charged (excess electron).
Thus, the rod becomes positively charged by transfer of electrons from rod to the silk.
e) electrons are transferred from the rod to the silk.
Answer:
1.56 J
Explanation:
given,
Spring compression, x = 2.5 cm
Force exerts by the spring,
F = - k x
k = 5000 N/m
Potential energy stored = ?
energy stored in the spring


PE = 1.56 J
Hence, the potential energy stored in the car is equal to 1.56 J.