Answer:
Explanation:
Object distance = distance between object and lens
u = 50 - 12 = 38 cm
image distance v = 88 - 50 = 38 cm
i )
using lens formula
1 / v - 1 / u = 1 / f
1 / 38 - 1 / - 38 = 1/f
2 / 38 = 1 / f
f = 19 cm
ii ) So object is placed at 2 f or at the center of curvature of the lens .
If object distance is changed to 50 - 31 = 19 cm
using lens formula
1 / v - 1 / u = 1 / f
1 / v + 1 / 19 = 1/19
1 / v = 0
v = infinity
It is so because now the object is placed at the focal distance
iii )
If object further shifts towards the lens , then virtual image of object will be formed behind the lens which will be larger than object .
Answer:
<em>The velocity of the ball as it hit the ground = 19.799 m/s</em>
Explanation:
Velocity: Velocity of a body can be defined as the rate of change of displacement of the body. The S.I unit of velocity is m/s. velocity is expressed in one of newtons equation of motion, and is given below.
v² = u² + 2gs.......................... Equation 1
Where v = the final velocity of the ball, g = acceleration due to gravity, s = the height of the ball
<em>Given: s = 20 m, u = 0 m/s</em>
<em>Constant: g = 9.8 m/s²</em>
<em>Substituting these values into equation 1,</em>
<em>v² = 0 + 2×9.8×20</em>
<em>v² = 392</em>
<em>v = √392</em>
<em>v = 19.799 m/s.</em>
<em>Therefore the velocity of the ball as it hit the ground = 19.799 m/s</em>
Answer:
2.62 m
Explanation:
Let the small child sit at a distance x from the pivot.
The distance of big child from the pivot is 4 - x .
By using the concept of moments.
Clockwise moments = anticlockwise moments
27 x = 51 ( 4 - x )
27 x = 204 - 51 x
78 x = 204
x = 2.62 m
Answer:
The shear modulus of the polymer is 5 MPa
Solution:
As per the question:
displacement of the top plate, d = 2 mm = 0.002 m
Horizontal Force, P = 2 kN = 2000 N
Width of the block, w = 100 mm = 0.1 m
By small angle analysis:
Angle,
Now,
Stress, =