Answer:
Stunt Car A experiences a large force over a short period of time. Stunt Car B experiences a small force over a long period of time. Because of the force experienced by Stunt Car A, it will sustain more damage than Stunt Car B.
Explanation:
Both cars have the same mass and velocity, therefore they have the same momentum. During the collision, the total momentum of the car A and brick wall is conserved as well as the total momentum of the car B and the pile of leaves.
However, if we are to investigate the damage on each car, we should look at the cars not the whole system. So, the momentum difference between the cars gives us the impulse that the car felt.
Since the Car A will crash the wall quicker than the other car crashes through the pile of leaves,
which gives us
Explanation :
Magnetic field, B = 5.2 T
Electric field, 
The directions of the two fields are perpendicular to each other. Hence the force due to each field will equate each other.
Electrostatic force, F =qE.........(1)
Magnetic force, F = qvB........(2)
From equation (1) and (2)
E = v B
Hence, the correct option is (a).
(2) A permanent magnet always has two poles as the North pole and south pole. The magnetic field lines start from north poles and terminate at the south pole of the magnet.
Hence, the correct option is (C).
Sound at 70 dB is 70 dB louder than the human reference level. That's 10⁷ times as much as the reference sound power.
Sound at 73 dB is 73 dB louder than the human reference level. That's 10⁷.³ or 2 x 10⁷ times as much as the reference sound power.
Sound at 80 dB is 80 dB louder than the human reference level. That's 10⁸ or 10 x 10⁷ times as much as the reference sound power.
Now we can adumup:
Intensity of all 3 sources = (10⁷) + (2 x 10⁷) + (10 x 10⁷)
Intensity = (13 x 10⁷) times the sound power reference intensity.
Intensity in dB = 10 log (13 x 10⁷) = 10 (7 + log(13)
Intensity = 70 + 10 log(13)
Intensity = 70 + 10 (1.114)
Intensity = 70 + 11.14
Intensity = <em>81.14 dB</em>
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Looking at the questioner's profile, I seriously wonder whether I'll ever get a comment in return from this creature, and how I'll ever find out if my solution is correct. For that matter, I'm also seriously questioning how and whether my solution will ever be used for anything.
There are two rules of reflection for the concave mirror:
1)<span>Any incident ray traveling parallel to the principal axis on the way to the mirror will pass through the focal point upon reflection.
2)</span><span>Any incident ray passing through the focal point on the way to the mirror will travel parallel to the principal axis upon reflection.
Also, keep in that for concave mirror center of curvature is 2f.
Using these two rules we can construct the image.
You should always use these two "special" rays, I will mark then 1 and 2 on the picture.
From the picture, we can see that if you place the object between the focus and vertex you get the virtual image.
The answer is: object should be between the focal point and the vertex</span>
