Answer:
Explanation:
Far point = 17 cm . That means he can not see beyond this distance .
He wants to see at an object at 65 cm away . That means object placed at 65 has image at 17 cm by concave lens . Using lens formula
1 / v - 1 / u = 1 / f
1 / - 17 - 1 / - 65 = 1 / f
= 1 / 65 - 1 / 17
= - .0434 = 1 / f
power = - 100 / f
= - 100 x .0434
= - 4.34 D .
Answer:
The initial velocity was 9.39 m/s
Explanation:
<em>Lets explain how to solve the problem</em>
The ball is thrown straight upward with initial velocity u
The ball reaches a maximum height of 4.5 m
At the maximum height velocity v = 0
The acceleration of gravity is -9.8 m/s²
We need to find the initial velocity
The best rule to find the initial velocity is <em>v² = u² + 2ah</em>, where v is
the final velocity, u is the initial velocity, a is the acceleration of
gravity and h is the height
⇒ v = 0 , h = 4.5 m , a = -9.8 m/s²
⇒ 0 = u² + 2(-9.8)(4.5)
⇒ 0 = u² - 88.2
Add 88.2 to both sides
⇒ 88.2 = u²
Take square root for both sides
⇒ u = 9.39 m/s
<em>The initial velocity was 9.39 m/s</em>
::Answer::
The answer you're looking for is Electrical Energy.
Newton's law of conservation states that energy of an isolated system remains a constant. It can neither be created nor destroyed but can be transformed from one form to the other.
Implying the above law of conservation of energy in the case of pendulum we can conclude that at the bottom of the swing the entire potential energy gets converted to kinetic energy. Also the potential energy is zero at this point.
Mathematically also potential energy is represented as
Potential energy= mgh
Where m is the mass of the pendulum.
g is the acceleration due to gravity
h is the height from the bottom z the ground.
At the bottom of the swing,the height is zero, hence the potential energy is also zero.
The kinetic energy is represented mathematically as
Kinetic energy= 1/2 mv^2
Where m is the mass of the pendulum
v is the velocity of the pendulum
At the bottom the pendulum has the maximum velocity. Hence the kinetic energy is maximum at the bottom.
Also as it has been mentioned energy can neither be created nor destroyed hence the entire potential energy is converted to kinetic energy at the bottom and would be equivalent to 895 J.
