Answer:
The vision becomes blurred due to the refractive defects of the eye. There are mainly three common refractive defects of vision. These are (i) myopia or near-sightedness, (ii) Hypermetropia or far – sightedness, and (iii) Presbyopia. These defects can be corrected by the use of suitable spherical lenses.
Answer:
About 1-3 km
Please follow me I will also follow you
Answer: 1.59 sec
Explanation:
The kinetic energy contained in the rotation of the cylinder is 1/2 m v^2
The kinetic energy of translation is also 1/2 m v^2
so the total energy is m v^2
The force applied is mg sin (theta)
= m x 9.8 x 1/2
= 4.9 m
Now equate
F x d = m v^2
4.9 m x 3.1 = m v^2
v^2 = 4.9 x 3.1
v = sqrt(4.9 x 3.1) = 3.9 m/s
Acceleration.
V^2 = 2 a s
4.9 x 3.1 = 2 x a x 3.1
4.9 = 2 a
a = 2.45 m/s^2
Time
T = v/a
= 3.9/2.45
= 1.59 sec
The plane has a centripetal acceleration <em>a</em> of
<em>a</em> = <em>v</em> ²/<em>r</em>
where <em>v</em> is the plane's tangential speed and <em>r</em> is the radius of the circle. By Newton's second law,
<em>F</em> = <em>mv</em> ²/<em>r</em>
Solve for the mass <em>m</em> :
<em>m</em> = <em>Fr</em>/<em>v</em> ² = (3000 N) (18.3 m) / (55.0 m/s)² ≈ 18.1 kg
The amount of heat needed to increase the temperature of a substance by
is given by
where
m is the mass of the substance
is its specific heat capacity
is the increase of temperature
The sample of silver of our problem has a mass of
. Its specific heat capacity is
and the increase in temperature is
Therefore, the amount of heat needed is
