Answer:
23 cm
Explanation:
The formula for magnification is;
Magnification = image distance / object distance
use values as;
3.2 = v / 30 where v is image distance
v =30*3.2
v=96 cm
The relationship of the focal length with image distance and object distance is expressed as;
where f is the focal length and u is object distance
use values in the equation as;
f=160/7
f=22.86
f= 23 cm ----------nearest a cm
Explanation:
In the first law, an object will not change its motion unless a force acts on it. In the second law, the force on an object is equal to its mass times its acceleration. In the third law, when two objects interact, they apply forces to each other of equal magnitude and opposite direction.
Answer with Explanation:
We are given that
Force acts on a pebble=
N
Position vector=
m
a.We have to find the resulting torque on the pebble about origin.
Torque=
Substitute the values then we get
Torque=
N-m
By using 
b.
Torque about point (2,0,-3)
N-m
Let us say that:
1 = 1st player notation
2 = 2nd player notation (the opponent)
a. First let us establish the distance travelled by the 2nd
player:
d2 = 13 m/s * (t + 1.5)
d2 = 13 t + 19.5
Then the distance of the 1st player:
d1 = v0 t + 0.5 a t^2 (v0
initial velocity = 0 since he started from rest)
d1 = 0.5 * 4 m/s^2 * t^2
d1 = 2 t^2
The two distances must be equal, d1 = d2:
2 t^2 = 13 t + 19.5
t^2 – 6.5 t = 9.75
Completing the square:
(t – 3.25)^2 = 9.75 + (- 3.25)^2
t – 3.25 = ±4.5
t = -1.25, 7.75
Since time cannot be negative, therefore:
t = 7.75 seconds
So he catches his opponent after 7.75 seconds.
b. Using the equation:
d1 = 2 t^2
d1 = 2 * (7.75)^2
d1 = 120.125 m
So he travelled about 120.125 meters when he catches up
to his opponent.
Answer:
Vibrations
Explanation:
That is why when under water it sounds muffled and you cannot hear clearly.
