Answer:
B. 4 m/s
Explanation:
v=d/t
Running for 300 m at 3 m/s takes 100 seconds and running at 300 m at 6 m/s takes 50 seconds. 100 s + 50 s = 150 s (total time). Total distance is 600 m, so 600 m/ 150 s = 4 m/s.
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
Question 1: Newtonian. It refers to work of Newton. Light, electrical and chemical energies are different forms of energy.
Question 2: Nuclear power plants. Heat , Sunlight and energy in atoms are not nuclear energies.
Question 3: Batteries. the other two are examples of mechanical energy. But batteries are examples for chemical energy.
The leaf fell at the crooked path instead of straight down because air currents and gravity applied changing and unbalanced forces to the leaf.
<h3>What is an air current?</h3>
An air current is defined as the changes in atmospheric pressure that causes the movement of air from one area to another.
When a leaf is detached naturally from the tree, it won't fall straight down to the floor but will fall a distance away from the tree due to the action of air current and some unbalanced forces.
Learn more about leaf here:
brainly.com/question/24234175
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