Answer:
Part a)

Part b)


Part c)
equation of position in x direction is given as

equation of position in y direction is given as

Part d)

Part e)
H = 88.5 m
Part f)
t = 1.2 s
Explanation:
As we know that ball is projected with speed
v = 8.10 m/s at an angle 18 degree below the horizontal
so we will have




Part a)
Since it took t =4 s to reach the ground
so its initial y coordinate is given as



Part b)
components of the velocity is given as




Part c)
equation of position in x direction is given as

equation of position in y direction is given as

Part d)
distance where it will strike the floor is given as



Part e)
Height from which it is thrown is same as initial y coordinate of the ball
so it is given as
H = 88.5 m
Part f)
time taken by ball to reach 10 m below is given as


t = 1.2 s
Answer:
30 cm
Explanation:
f = Focal length = 25 cm
R = Radius of curvature (both sides are equal)
= Refractive index of lens = 1.6
The lens maker formula is given by
minus sign because it is on the other side

The radius of curvature of the glass surface is 30 cm
I believe the answer is D
Hope this helps :)
Elastic Potential Energy because the elasticity in the string stores up the energy.
Answer:
but where are the options?