Answer:
The correct solution is:
(a) 
(b) 
(c) 
(d) 
Explanation:
The given values are:
Effective duration of the flash,
ζ = 0.25 s
Average power,
Average voltage,
Now,
(a)
⇒ 
On substituting the values, we get
⇒ 
⇒ 
(b)
⇒ 
then,
⇒ 
On substituting the values, we get
⇒ 
⇒ 
(c)
⇒ 
⇒ 
⇒ 
(d)
As we know,
⇒ 
⇒ 
⇒ 
⇒ 
The answer would be number four. I'm sorry if I am too late. Byes.....
Answer:
the ball's velocity was approximately 0.66 m/s
Explanation:
Recall that we can study the motion of the baseball rolling off the table in vertical component and horizontal component separately.
Since the velocity at which the ball was rolling is entirely in the horizontal direction, it doesn't affect the vertical motion that can therefore be studied as a free fall, where only the constant acceleration of gravity is affecting the vertical movement.
Then, considering that the ball, as it falls covers a vertical distance of 0.7 meters to the ground, we can set the equation of motion for this, and estimate the time the ball was in the air:
0.7 = (1/2) g t^2
solve for t:
t^2 = 1.4 / g
t = 0.3779 sec
which we can round to about 0.38 seconds
No we use this time in the horizontal motion, which is only determined by the ball's initial velocity (vi) as it takes off:
horizontal distance covered = vi * t
0.25 = vi * (0.38)
solve for vi:
vi = 0.25/0.38 m/s
vi = 0.65798 m/s
Then the ball's velocity was approximately 0.66 m/s
Answer:
Cork
Explanation:
Cork is a solid, other ones are fluid.
Answer:
1.414
Explanation:
Snell's law states:
n₁ sin θ₁ = n₂ sin θ₂
where n is the index of refraction and θ is the angle of incidence (relative to the normal).
The index of refraction of air is approximately 1. So:
1 sin 45° = n sin 30°
n = sin 45° / sin 30°
n = 1.414
Round as needed.
