Answer:
0.125 cm
Explanation:
1/f = 1/d¡ + 1/d。
Find the focal point
(13.0^-1 + 20.8^-1) = 0.125 m
Focal point = 0.125 m
Answer:
Tension = 0.012 N
Explanation:
If the black widow spider is hanging vertically motionless from the ceiling above. Then, the weight of the spider must be balancing the tension in the spider web. Therefore,
Tension = Weight
Tension = mg
where,
m = mass of spider = 1.27 g = 0.00127 kg
g = acceleration due to gravity = 9.8 m/s²
Therefore,
Tension = (0.00127 kg)(9.8 m/s²)
<u>Tension = 0.012 N</u>
initial speed of 226000 m/s
acceleration of 4.0 x 1014 m/s2,
speed of 781000 m/s
What is Acceleration?
- Acceleration is a rate of change of velocity with respect to time with respect to direction and speed.
- A point or an object moving in a straight line is accelerated if it speeds up or slows down.
- Acceleration formula can be written as,
a = (v - u ) / t m/s²
As we have to find the time taken, the formula can be altered as,

where, t - time taken to reach a final speed
v - final velocity
u - initial velocity
a - acceleration.
Substituting all the given values,

= 1.3875 × 10⁻⁹ seconds.
So, taken to reach the final speed is found to be 1.3 × 10⁻⁹ 8iH..
Answer:
The near point of an eye with power of +2 dopters, u' = - 50 cm
Given:
Power of a contact lens, P = +2.0 diopters
Solution:
To calculate the near point, we need to find the focal length of the lens which is given by:
Power, P = 
where
f = focal length
Thus
f = 
f =
= + 0.5 m
The near point of the eye is the point distant such that the image formed at this point can be seen clearly by the eye.
Now, by using lens maker formula:

where
u = object distance = 25 cm = 0.25 m = near point of a normal eye
u' = image distance
Now,



Solving the above eqn, we get:
u' = - 0.5 m = - 50 cm