Newton's 2nd law of motion: Force = (mass) x (acceleration)
If you want to move a 7-kg object with an acceleration of 4 m/s²,
then you will need to push it with (7 x 4) = 28 newtons of force.
Answer:
The lenses with different focal length are four.
Explanation:
Given that,
Radius of curvature R₁= 4
Radius of curvature R₂ = 8
We know ,
Refractive index of glass = 1.6
When, R₁= 4, R₂ = 8
We need to calculate the focal length of the lens
Using formula of focal length
Put the value into the formula
When , R₁= -4, R₂ = 8
Put the value into the formula
When , R₁= 4, R₂ = -8
Put the value into the formula
When , R₁= -4, R₂ = -8
Put the value into the formula
Hence, The lenses with different focal length are four.
True, the path of the ball, as observed from the train window, will be a horizontal straight line.
An object projected from a certain height has a parabolic path when observed from a fixed point.
However, if the reference point is moving at the same velocity as the object, the path of the object's motion appears to be a straight line.
When the ball is released from the window of the train, it will move at the same constant velocity as the train, and the path of the ball's motion observed from the train window will be a straight line.
Thus, we can conclude that the given statement is true. The path of the ball, as observed from the train window, will be a horizontal straight line.
Learn more about path of motion of objects here: brainly.com/question/82610
