It is given that for the convex lens,
Case 1.
u=−40cm
f=+15cm
Using lens formula
v
1
−
u
1
=
f
1
v
1
−
40
1
=
15
1
v
1
=
15
1
−
40
1
v=+24.3cm
The image in formed in this case at a distance of 24.3cm in left of lens.
Case 2.
A point source is placed in between the lens and the mirror at a distance of 40 cm from the lens i.e. the source is placed at the focus of mirror, then the rays after reflection becomes parallel for the lens such that
u=∞
f=15cm
Now, using mirror’s formula
v
1
+
u
1
=
f
1
v
1
+
∞
1
=
15
1
v=+15cm
The image is formed at a distance of 15cm in left of mirror
The best thing to do is start out small. Do something that is in your comfort zone and get bigger each time. Before you know it, you will have gotten over your fear and it'll feel great :)
did you mean what activities are performed during the cool down?
The time taken by the stone to hit the ground would be 5.12 seconds.
<h3>What are the three equations of motion?</h3>
There are three equations of motion given by Newton
The first equation is given as follows
v = u + at
the second equation is given as follows
S = ut + 1/2×a×t²
the third equation is given as follows
v² - u² = 2×a×s
Keep in mind that these calculations only apply to uniform acceleration.
As given in the problem, a stone is dropped from the helicopter which is ascending at the speed of 19.6 m/s
height(S) = 156.8 meters
initial velocity(u) = -19.6 m/s
acceleration(a) = 9.81 m/s²
By using the second equation of motion given by newton
S = ut + 1/2at²
S = 156.8m ,u= -19.6 m/s , a= 9.81 m/s² and t =? seconds
156.8= -19.6t + 9.81t²
t = 5.12 seconds
Thus, the time taken by the stone to hit the ground would be 5.12 seconds.
Learn more about equations of motion from here,
brainly.com/question/5955789
#SPJ1