Second option would be correct.
Heya!
For this problem, use the formula:
s = Vo * t + (at^2) / 2
Since the initial velocity is zero, the formula simplifies like this:
s = (at^2) / 2
Clear a:
2s = at^2
(2s) / t^2 = a
a = (2s) / t^2
Data:
s = Distance = 518 m
t = Time = 7,48 s
a = Aceleration = ¿?
Replace according formula:
a = (2*518 m) / (7,48 s)^2
Resolving:
a = 1036 m / 55,95 s^2
a = 23,34 m/s^2
The aceleration must be <u>23,34 meters per second squared</u>
Answer: I added a picture of the answer
Explanation: its right
Let's see sentence-by-sentence:
<span>- Objects within the focal length will create real images. --> false
In fact, objects within the focal length create virtual images, as it can be seen in the ray diagrams here:
https://upload.wikimedia.org/wikipedia/commons/4/47/Concavemirror_raydiagram_F.svg
- Concave mirrors converge distant parallel light rays on the focal point. --> TRUE: the parallel rays (with respect to the mirror's axis) are reflected back into the focal point of the mirror, as it can be seen also from the previous picture.
- Concave mirrors can only create real images. --> FALSE: as it can be seen from the first picture, when the object is between the focus and the mirror, its image is virtual.
Concave mirrors can create real and virtual images. --> TRUE: concave mirrors can create real and virtual images, depending on the position of the object.
- Objects far away from concave mirrors will appear enlarged. --> FALSE:
as it can be seen from the ray diagram, the size of the image is smaller than the size of the object. https://upload.wikimedia.org/wikipedia/commons/d/d2/Concavemirror_raydiagram_2F.svg
- Objects between the center of curvature and the focal point will create real images.--> TRUE: as it can be seen from the ray diagram (2F corresponds to the center of curvature), the image in this case is on the same side of the object, so it is real. </span>https://upload.wikimedia.org/wikipedia/commons/9/91/Concavemirror_raydiagram_2FE.svg
Answer:
A. 1.8x10⁵
Explanation:
For this question we have
72km/h = speed
Total mass = 2250kg
Stopped at t = 0.2250s
To get average force acting on this car on collision:
72km/3.6 = 20m|s
Impulse = ∆p
This implies:
F∆t = m∆v
F = m∆v/∆t
= 2250x20/0.250
= 180000
= 1.8x10⁵
Therefore option A is correct.
