The board is 2.50m high.
Why?
We can calculate how high was the board applying the Law of Conservation of Mechanical Energy. This Law states that the mechanical energy (kinematic and potential) will be conserved during the motion.
It can be described with the following formula:


At the top of the boar, the kinetic energy is equal to 0.
At the water, the potential energy is equal to 0.
So,

Hence, we have that the board is 2.50m high.
Have a nice day!
We need optics to help aid people who have short or long sightedness.
we need optics to be able to watch TV
we need optics to be able to use the internet at high speeds
there are a tonne of reasons why we need optics.
Please solve it ,,,,,,,,,,................................
fredd [130]
Answer:
the distance covered by the body in 5th second =u+a(n- 1/2)=7+4(5- 1/2)
=7+4×9/2
=7+18
=25m
Answer:
6.37 x 10³ Km
Explanation:
given,
Radius of earth = 6,370,000 m
we know,
1 km = 1000 m
1 m = 0.001 Km
6,370,000 m = 6,370,000 x 0.001
= 6,370 Km
The number 6,370 has 3 significant figure.
To transform this to an exponential number, it is necessary to move the decimal to the left so there is only one digit in front of the decimal point.
Representing the given number in scientific notation
= 6.37 x 10³ Km