Answer:
v = 9.936 m/s
Explanation:
given,
height of cliff = 40 m
speed of sound = 343 m/s
assuming that time to reach the sound to the player = 3 s
now,
time taken to fall of ball
t = 2.857 s
distance
d = v x t
d = v x 2.875
time traveled by the sound before reaching the player
distance traveled by the wave in this time'
r = 0.143 x 343
r= 49.05 m
now,
we know.
d² + h² = r²
d² + 40² = 49.05²
d =28.387 m
v x 2.875=28.387 m
v = 9.936 m/s
Answer:
beam of light converges to a point A. A lens is placed in the path of the convergent beam 12 cm from P.
To find the point at which the beam converge if the lens is (a) a convex lens of focal length 20 cm, (b) a concave lens of focal length 16 cm
Solution:
As per the given criteria,
the the object is virtual and the image is real (as the lens is placed in the path of the convergent beam)
(a) lens is a convex lens with
focal length, f=20cm
object distance, u=12cm
applying the lens formula, we get
f
1
=
v
1
−
u
1
⟹
v
1
=
f
1
+
u
1
⟹
v
1
=
20
1
+
12
1
⟹
v
1
=
60
3+5
⟹v=7.5cm
Hence the image formed is real, at 7.5cm from the lens on its right side.
(b) lens is a concave lens with
focal length, f=−16cm
object distance, 12cm
applying the lens formula, we get
f
1
=
v
1
−
u
1
⟹
v
1
=
f
1
+
u
1
⟹
v
1
=
−16
1
+
12
1
⟹
v
1
=
48
−3+4
⟹v=48m
Hence the image formed is real, at 48 cm from the lens on the right side.
To develop this problem it is necessary to apply the concepts related to the uni-axial deflection of bodies.
From the expression of Hooke's law we have to
Where,
E= Young's modulus
The strain
And substituting P/A for stress and 
for strain gives that
Where,
P = Force
A = Area
L = Length
Therefore this can be re-arranged to give
If we want to calculate the deformation per unit area then we can also rewrite the equation as
Replacing with our values we have to
Therefore the posion ratio would be
Therefore the Poisson's ratio for this material is 0.4238
The volcanoes and earthquakes that are along the ring of fire are caused by the amount of movement of tectonic plates in the area. Plates overlap at convergent boundaries called subduction zones. As rock is subducted, it melts and becomes magma.
Hope this helps! :)
